Thermally imageable dielectric layers, thermal transfer donors and receivers

ABSTRACT

The invention is related to thermal imageable dielectric layers and thermal transfer donors and receivers comprising dielectric layers. The thermal transfer donors are useful in making electronic devices by thermal transfer of dielectric layers having excellent resistivity, good transfer properties and good adhesion to a variety of receivers.

This invention was made with United States Government support underAgreement No. 70NANB2H03032 awarded by NIST Advanced Technology Program.The United States Government has certain rights in the invention.

FIELD OF INVENTION

The invention relates to polymer/dye compositions, dielectric layers andthermal transfer donors useful for printing dielectric layers forelectrical applications.

BACKGROUND

Thermal transfer processes are well known in applications such as colorproofing as a means of dry transferring or printing of dye and/orpigment layers. Such thermal transfer processes typically use a laser toinduce the image-wise thermal transfer of material.

Laser-induced thermal transfer processes typically use a donor element,including a layer of material to be transferred, referred to herein as atransfer layer, and a receiver element, including a surface forreceiving the transferred material. Either the substrate of the donorelement or the receiver element is transparent, or both are transparent.The donor element and receiver element are brought into close proximityor into contact with each other and selectively exposed to laserradiation, usually by an infrared laser. Heat is generated in theexposed portions of the transfer layer, causing the transfer of thoseportions of the transfer layer onto the surface of the receiver element.If the material of the transfer layer does not absorb the incoming laserradiation, the donor element should include a heating layer, also knownas a light-to-heat conversion (LTHC) layer or a transfer-assist layer,in addition to the transfer layer.

In a typical laser-induced digital thermal transfer process the exposuretakes place only in a small, selected region of the assembly at a time,so that transfer of material from the donor element to the receiverelement can be built up one region at a time. The region may be a pixel,some portion of a pixel or a plurality of pixels. Computer controlfacilitates the transfer at high speed and high resolution.Alternatively, in an analog process, the entire assembly is irradiatedand a mask is used to selectively expose desired portions of thethermally imageable layer.

A particular need for printable electronics includes thermally imageableinsulating layers or dielectric passivation layers. WO 2005/004205, forinstance, discloses a method of forming a pattern of filled dielectricmaterial on a substrate by a thermal transfer process comprisingexposing to heat a thermally imageable donor element comprising a basefilm, a light to heat conversion (LTHC) layer, and a transfer layer ofdielectric material. In a thin film transistor (TFT), the dielectriclayer serves to insulate the gate layer from the semiconductor andsource-drain layers. Its primary function is to allow the passage offields, but not currents. A fundamental requirement is that thedielectric layer possess high volume resistivity, greater than 10¹⁴ohm-cm, to prevent leakage currents; and be largely pinhole free toprevent catastrophic shorts between conductive layers. The dielectriclayer also must have high purity in order not to dope the adjacentsemiconductor layer; it should be thin, for instance, about 5 microns orless, and have a high dielectric constant for low-voltage operation.

Additional requirements for successful thermal transfer of thedielectric layer include: the dielectric composition must be coatableand therefore must have adequate solubility and/or dispersability in asuitable solvent; it must exhibit good interfacial behavior (mechanical,electrical) with adjacent layers, including the receiver, the conductinglayers (gate and source-drain layers) and the semiconductor layer; andit must be printable by thermal transfer and maintain its insulatingproperties. In order for an insulating layer to meet this lastrequirement and be printed in one printing cycle, it needs to exhibitgood adhesion to all previous layers including receiver, conductinglayers and semiconductor layers. It must print under approximately thesame conditions (e.g., same drum speed and power) onto all of thedifferent previous layers, and it must print with acceptable quality.For example, defects caused by the thermal transfer process including:pinholes, bubbles, cohesive failure, breaks at swath boundaries, andco-transfer of materials from the adjacent donor substrate layers(typically the LTHC layer); must be very minimal in order not to degradeelectrical performance to an unacceptable level.

There is a need for thermal transfer donors that allow patterned thermaltransfer of dielectric layers with excellent resistivity that exhibitgood transfer properties and good adhesion to a variety of materials.Particularly desirable are thermal transfer donors wherein, aftertransfer, the patterned layer has the uniformity, continuity andresistive properties required of a dielectric layer in electricalapplications, for instance in applications for capacitors or thin filmtransistors.

SUMMARY OF INVENTION

One aspect of the invention is a composition, comprising: (a) one ormore dielectric polymer(s) selected from the group consisting of:acrylic and styrenic polymers selected from the group consisting of:acrylic, styrenic and styrenic-acrylic latexes, solution-based acrylic,styrenic and styrenic-acrylic polymers, and combinations thereof;heteroatom-substituted styrenic polymers selected from the groupconsisting of: partially hydrogenated poly(4-hydroxy)styrene,poly(4-hydroxy)styrene, and copolymers of poly(4-hydroxy)styrene withhydroxyethyl(meth)acrylate, alkyl(meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group; phenol-aldehyde (co)polymers and(co)oligomers and combinations thereof; and poly(vinyl acetate); and (b)about 0.5 wt % to about 10 wt %, based on a dry weight of thecomposition, of one or more near-IR dye(s); wherein a dry layercomprising said composition has a resistivity of 10¹⁴ ohm-cm or greaterand has an absorption maximum in the range of about 600 to about 1200nm.

Another aspect of the invention is a dielectric layer, with aresistivity of about 10¹⁴ ohm-cm or greater, comprising at least oneLayer A, comprising: (a) one or more dielectric polymer(s) selected fromthe group consisting of: acrylic and styrenic polymers selected from thegroup consisting of: acrylic, styrenic and styrenic-acrylic latexes,solution-based acrylic, styrenic and styrenic-acrylic polymers, andcombinations thereof; heteroatom-substituted styrenic polymers selectedfrom the group consisting of: partially hydrogenatedpoly(4-hydroxystyrene), poly(4-hydroxystyrene), and copolymers ofpoly(4-hydroxystyrene) with hydroxyethyl(meth)acrylate,alkyl(meth)acrylate, styrene, and alkyl-substituted styrene wherein thealkyl group is a C1 to C18 straight or branched chain alkyl group;phenol-aldehyde (co)polymers and (co)oligomers and combinations thereof;and poly(vinyl acetate); and (b) about 0.5 wt % to about 10 wt %, basedon a dry weight of LayerA, of one or more near-IR dye(s) having anabsorption maximum in the range of about 600 to about 1200 nm withinLayer A.

Another aspect of the invention is a multilayer thermal imaging donorcomprising: (a) a base film; and (b) a dielectric transfer layercomprising at least one Layer A comprising: one or more dielectricpolymer(s) selected from the group consisting of: acrylic and styrenicpolymers selected from the group consisting of: acrylic, styrenic andstyrenic-acrylic latexes, solution-based acrylic, styrenic andstyrenic-acrylic polymers, and combinations thereof;heteroatom-substituted styrenic polymers selected from the groupconsisting of: partially hydrogenated poly(4-hydroxystyrene),poly(4-hydroxystyrene), and copolymers of poly(4-hydroxystyrene) withhydroxyethyl(meth)acrylate, alkyl(meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group; phenol-aldehyde (co)polymers and(co)oligomers and combinations thereof; and poly(vinyl acetate); andabout 0.5 wt % to about 10 wt %, based on the dry weight of Layer A, ofone or more near-IR dye(s) having an absorption maximum in the range of600 to about 1200 nm within Layer A; wherein the dielectric transferlayer has a resistivity of 10′⁴ ohm-cm or greater.

BRIEF DESCRIPTION OF FIGURES

FIG. 1A is a cross-sectional view of a thermal imaging donor 100comprising a dielectric transfer layer 106 and a base film 102.

FIG. 1B is a cross-sectional view of a thermal imaging donor 100comprising a LTHC layer 108.

FIG. 2A is a cross-sectional view of a thermal imaging donor 100comprising an interlayer layer 104.

FIG. 2B is a cross-sectional view of a thermal imaging donor comprisinga LTHC layer 108 interposed between base film 102 and an interlayer 104.

FIG. 3A, 3B and 3C are cross-sectional views of thermal imaging donors100 comprising multiple dielectric transfer layers.

FIG. 4 is a cross-sectional view of a thermal imaging receiver 200comprising a receiver base film 202 and optional adhesive layer 204.

FIGS. 5A and 5B illustrate the donor 100 and receiver 200 after transferof an exposed portion of the dielectric transfer layer.

FIG. 6 illustrates the current versus gate voltage sweep with drain isvoltage equal −50 V for the transistor made with the dielectrics layersaccording to one embodiment of the invention.

DETAILED DESCRIPTION

Herein the terms “acrylic”, “acrylic resin”, “(meth)acrylic resins”, and“acrylic polymers”, are synonymous unless specifically definedotherwise. These terms refer to the general class of addition polymersderived from the conventional polymerization of ethylenicallyunsaturated monomers derived from methacrylic and acrylic acids andalkyl and substituted-alkyl esters thereof. The terms encompasshomopolymers and copolymers. The terms encompass specifically thehomopolymers and copolymers of methyl(meth)acrylate,ethyl(meth)acrylate, butyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate,(meth)acrylic acid and glycidyl(meth)acrylate. The term copolymer hereinencompasses polymers derived from polymerization of two or moremonomers, unless specifically defined otherwise. The term (meth)acrylicacid encompasses both methacrylic acid and acrylic acid. The term(meth)acrylate, encompasses methacrylate and acrylate.

The terms “styrene acrylic polymers”, “acrylic styrene” and “styreneacrylic” are synonymous and encompass copolymers of the above described“acrylic resins” with styrene and substituted styrene monomers, forinstance alpha-methyl styrene.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive or and not to an exclusive or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

Also, use of “a” or “an” are employed to describe elements andcomponents described herein. This is done merely for convenience and togive a general sense of the scope of the invention. This descriptionshould be read to include one or at least one and the singular alsoincludes the plural unless it is obvious that it is meant otherwise.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although methods and materialssimilar or equivalent to those described herein can be used in thepractice or testing of embodiments of the present invention, suitablemethods and materials are described below. All publications, patentapplications, patents, and other references mentioned herein areincorporated by reference in their entirety, unless a particular passageis cited. In case of conflict, the present specification, includingdefinitions, will control. In addition, the materials, methods, andexamples are illustrative only and not intended to be limiting.

Dielectric Layers and Compositions

One embodiment of the invention is a dielectric layer having aresistivity of about 10¹⁴ ohm-cm or greater comprising at least onelayer of material, herein referred to as Layer A, comprising: one ormore dielectric polymers selected from the group consisting of: acrylicand styrenic polymers selected from the group consisting of: acrylic,styrenic and styrenic-acrylic latexes, solution-based acrylic, styrenicand styrenic-acrylic polymers, and combinations thereof;heteroatom-substituted styrenic polymers selected from the groupconsisting of: partially hydrogenated poly(4-hydroxy)styrene,poly(4-hydroxy)styrene, and copolymers of poly(4-hydroxy)styrene withhydroxyethyl(meth)acrylate, alkyl(meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group; phenol-aldehyde (co)polymers and(co)oligomers and combinations thereof; and poly(vinyl acetate; andabout 0.5 wt % to about 10 wt %, based on the dry weight of Layer A, ofone or more near-IR dye(s) having an absorption maximum in the range ofabout 600 to about 1200 nm within Layer A. In a preferred embodiment thedielectric layer consists essentially of one or more of the dielectricpolymers and about 0.5 wt % to about 10 wt %, of one or more near-IRdye(s) described herein. The term dielectric polymers herein encompasseshomopolymers, copolymers derived from polymerization of two or moremonomers, post-derivatized (co)polymers including graft (co)polymers,and low molecular weight homopolymers or copolymers. The polymers may belinear, branched, hyperbranched or dendritic.

Preferred dielectric polymers for Layer A include acrylic, styrenic andstyrenic-acrylic latexes comprising alkyl(meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group. Preferred optional monomers forthese latex-based polymers include (meth)acrylic acid,hydroxyethyl(meth)acrylate and glycidyl(meth)acrylate. More preferredacrylic, styrenic and styrenic-acrylic latexes are selected from thegroup consisting of: Latexes A, defined herein as one or more latexresins comprising at least about 85 wt %, preferably at least about 90wt %, and more preferably at least about 95 wt %, of monomers selectedfrom the group: alkyl(meth)acrylate, styrene, and alkyl-substitutedstyrene wherein the alkyl group is a C1 to C18 straight or branchedchain alkyl group. Preferred optional monomers for these latex resinsinclude (meth)acrylic acid, preferably up to about 5 wt %,hydroxyethyl(meth)acrylate, preferably up to about 10 wt %, andglycidyl(meth)acrylate, preferably up to about 5 wt %. Preferably thelatexes have an average particle size of less than about 150 nm, morepreferably, less than about 100 nm, and an acid number less than about100. preferably less than about 75, and more preferably less than about25.

Particularly preferred polymers for Layer A are Acrylic Latexes B andStyrene Acrylic Latexes C and combinations thereof. Acrylic Latexes Bare defined herein as one or more acrylic latexes comprising at leastabout 85 wt %, preferably at least about 90 wt %, and more preferably atleast about 95 wt %, of monomers selected from the group consisting of:methyl methacrylate and butyl acrylate. Styrene Acrylic Latexes C aredefined herein as one or more styrene-acrylic latexes comprising atleast about 85 wt %, preferably at least about 90 wt %, and morepreferably at least about 95 wt %, of monomers selected from the groupconsisting of: methyl methacrylate, butyl acrylate and styrene.Preferred optional monomers for Acrylic Latexes B and Styrene AcrylicLatexes C include: (meth)acrylic acid, preferably up to about 5 wt %,hydroxyethyl methacrylate, preferably up to about 10 wt %, and glycidylmethacrylate, preferably up to about 5 wt %.

Commercial examples of acrylic and styrenic acrylic latexes useful asdielectric polymers include Joncryl® 95 and 1915 (co)polymers (JohnsonPolymer). Methods for synthesizng suitable latex polymers have beenreported in WO 03/099574.

Further preferred dielectric polymers for Layer A include solution-basedacrylic, styrenic and styrenic-acrylic polymers. Herein the term“solution-based” refers to materials that are soluble in solvents suchas water and/or one or more common organic solvents including alcohols,e.g. ethanol and butoxyethanol; ethers, e.g. dimethoxyethane; esters,e.g. ethyl and butyl acetate; ketones, e.g., acetone and 2-butanone; andaromatic hydrocarbons, e.g. xylenes. Preferred solution-based acrylic,styrenic and styrenic-acrylic polymers have a M_(w) of less than about100,000, preferably less than 50,000, and more preferably less than30,000. Furthermore, preferred solution-based acrylic, styrenic andstyrenic-acrylic polymers have an acid number less than about 250.Preferred solution-based acrylic, styrenic and styrenic-acrylic polymerscomprise alkyl(meth)acrylate, benzyl (meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group. Preferred optional monomers forthese solution-based polymers include (meth)acrylic acid andhydroxyethyl(meth)acrylate.

A particularly preferred material for Layer A is a combination of theacrylic, styrenic and styrenic-acrylic latexes and water-based acrylic,styrenic and styrenic-acrylic polymers described above. Preferably thecombination comprises about 20 wt % to about 80 wt %, more preferablyabout 40 wt % to about 80 wt %, of an acrylic or styrenic-acrylic latexfraction and about 20 wt % to about 80 wt %, more preferably about 20 wt% to about 60 wt %, of a water-based acrylic or styrenic-acrylic polymerfraction, based on the dry weight of the combination.

Other preferred dielectric polymers for Layer A includeheteroatom-substituted styrenic polymers selected from the groupconsisting of: partially hydrogenated poly(4-hydroxy)styrene,poly(4-hydroxy)styrene (PHS), and copolymers of PHS withhydroxyethyl(meth)acrylate, alkyl(meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group. Particularly preferredcomonomers are hydroxyethyl methacrylate, butyl acrylate, methylmethacrylate and styrene with hydroxyethylmethacrylate and butylacrylate being especially preferred. The PHS (co)polymers may be linearor branched. When PHS homopolymer is used, the branched structure ispreferred Preferred (co)polymers of this class have a M_(w) of less thanabout 30,000 and preferably less than about 20,000 and more preferablyless than about 10,000. Partially hydrogenated PHS refers to PHSpolymers that have been hydrogenated up to about 50 equivalent % of theunsaturation within the polymer and preferred polymers are hydrogenatedto about 10 to 20 equivalent %. Commercial examples include PHS-B(branched PHS homopolymer; DuPont Electronic Technologies, Dallas,Tex.), Maruka Lyncur CMM (PHS copolymer with methyl methacrylate;Maruzen Petrochemical Co., LTD. Tokyo, Japan), Maruka Lyncur CHM (PHScopolymer with hydroxyethyl methacrylate; Maruzen), Maruka Lyncur CBA(PHS copolymer with buyl acrylate, Maruzen), Maruka Lyncur CST 15, 50,and 70 (PHS copolymers with styrene, Maruzen), and Maruka Lyncur PHM-C(partially hydrogenated PHS, Maruzen).

Other preferred dielectric polymers for Layer A include those selectedfrom the group consisting of: phenol-aldehyde (co)polymers/(co)oligomersand combinations thereof. Preferred (co)polymers/(co)oligomers in thisclass are derived from mono- and bis-phenols and mono- and bis-aldehydesselected from the group consisting of: phenol; alkyl- andaryl-substituted phenols; formaldehyde; and alkyl-, aryl- andheteroatom-substituted aldehydes. The phenol-aldehyde resins can befurther derivatized, e.g., the hydroxy group converted to an ethergroup. Preferred (co)polymers/(co)oligomers within this group have aM_(w) of about 20,000 or less, preferably about 10,000 or less.Commercial examples include Novolac®/Novolak® resins (SchenectadyInternational Inc., Schenectady N.Y.).

Other preferred dielectric polymers for Layer A include poly(vinylacetate) homopolymer. Preferred polymers within this group have a M_(w)of about 100,000 or less.

The above polymers may be plasticized for improved flexibility,adhesion, compatibilization with an IR dye, among other characteristics.In certain instances, the plasticizer may be selected from the aboveclasses of polymers. For example, a higher Tg or higher molecular weight(MW) phenol-aldehyde polymer can be blended with a lower Tg or lower MWphenol-aldehyde polymer. Another example is PHS blended with aphenol-aldehyde polymer. Examples of suitable plasticizers for some ofthe above classes of polymers comprise poly(ethylene) glycol, glycerolethoxylate, di(ethyleneglycol) dibenzoate, and phthalate-basedplasticizers such as dibutyl phthalate. A number of potentially suitableplasticizers for various polymers and details regarding their use may befound in the following reference: “Handbook of Plasticizers,” Ed. G.Wypych, ChemTec Publishing, Toronto, Ont. 2004.

The dielectric Layer A comprises about 0.5 wt % to about 10 wt %, andmore preferably about 0.5 wt % to about 6 wt %, based on the dry weightof the layer of material, of one or more near-IR dye(s) having anabsorption maximum in the range of about 600 to about 1200 nm within thelayer of material. Preferably the near-IR dye is chosen such that itsabsorption band overlaps with the emission band of the exposure laserused in the transfer process. Typically, the exposure laser emitsradiation in the near-IR range. Preferred classes of dyes are thecyanine compound(s) selected from the group consisting of: indocyanines,phthalocyanines including polysubstituted phthalocyanines andmetal-containing phthalocyanines, and merocyanines. A particularlypreferred class of near-IR dye(s) is that of indocyanine dyes,preferably having absorption at about 830 nm. A number of suitableindocyanine dyes absorbing at around 830 nm and with solubility indifferent solvents and in water are available from H. W. Sands Co. andother sources. Preferred near-IR dyes for the invention are selectedfrom the group: 3H-indolium,2-[2-[2-chloro-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)ethylidene]-1-cyclopenten-1-yl]ethenyl]-1,3,3-trimethyl-,salt with trifluoromethanesulfonic acid (1:1) having CAS No.[128433-68-1];2-(2-(2-chloro-3-(2-(1,3-dihydro-1,1-dimethyl-3-(4-sulphobutyl)-2H-benz[e]indol-2-ylidene)ethylidene)-1-cyclohexene-1-yl)ethenyl)-1,1-dimethyl-3-(4-sulphobutyl)-1H-benz[e]indolium,inner salt, free acid having CAS No. [162411-28-1]; and indolenine dyescorresponding to formulas (I) and (II) and resonance structures thereof:

Preferred dye levels in the material will give a film OD of about 0.2 orgreater, with an OD of about 0.5 to about 1.5 being preferred. To reacha preferred OD, unfilled water-based latex systems will typicallyrequire a higher dye loading of about 4 to 6 wt %. Unfilledsolution-based systems will typically require lower dye loadings ofabout 0.5 to about 2 wt %.

In another embodiment the dielectric layer comprises two or more LayersA that are gradient dye layers with each gradient dye layerindependently having a dry wt % of near-IR dye of about 0.5 to about 10wt %; wherein at least one gradient dye layer has a lower wt % ofnear-IR dye, at least one gradient dye layer has a higher wt % ofnear-IR dye, and said higher wt % of near-IR dye is a value at least 20%higher than that of the lower wt % of near-IR dye.

In another embodiment Layer A further comprises a high κ (highdielectric constant) nanoparticle fraction, of about 10 to about 90 wt %based on the dry weight of Layer A, with the nanoparticle fractionhaving a dielectric constant greater than about 20, and an averageparticle size of about 5 nm to about 500 nm. Herein high κ dielectricnanoparticle fraction refers to nanoparticles with a dielectric constantof about 20 and above, preferably about 30 and above, and morepreferably about 100 and above. Preferred dielectric polymers forpracticing this embodiment are selected from the group consisting of:acrylic and styrenic-acrylic latexes, solution-based acrylic andstyrenic-acrylic (co)polymers, and combinations thereof; andphenol-aldehyde (co)polymers/(co)oligomers; as described above.Preferred high κ dielectric nanoparticles for practicing this embodimentare is selected from the group consisting of: barium titanate, strontiumtitanate, barium strontium titanate and titanium dioxide.

In another embodiment the dielectric layer comprises two or more LayersA that are gradient nanoparticle layers with each gradient nanoparticlelayer independently having a dry wt % of high κ nanoparticle fraction ofabout 10 to about 90 wt %; wherein at least one gradient nanoparticlelayer has a lower wt % of high κ nanoparticle fraction and at least onegradient nanoparticle layer has a higher wt % of high κ nanoparticlefraction, and said higher wt % of high κ nanoparticle fraction is avalue at least 20% higher than that of the lower wt %.

In another embodiment the dielectric layer further comprises anadditional dielectric layer, herein referred to as Layer B, comprisingone or more dielectric polymers, having a resistivity of about 10¹⁴ohm-cm or greater. Extensive lists of dielectric polymers can be foundin WO 03/052841 and WO 06/024012. Preferred dielectric polymers forLayer B are selected from the group consisting of: acrylic and styrenicpolymers selected from the group: acrylic, styrenic and styrenic-acryliclatexes, solution-based acrylic, styrenic and styrenic-acrylic polymers,and combinations thereof; heteroatom-substituted styrenic polymersselected from the group consisting of: partially hydrogenatedpoly(4-hydroxy)styrene, poly(4-hydroxy)styrene, and copolymers ofpoly(4-hydroxy)styrene with hydroxyethyl(meth)acrylate,alkyl(meth)acrylate, styrene, and alkyl-substituted styrene wherein thealkyl group is a C1 to C18 straight or branched chain alkyl group;phenol-aldehyde (co)polymers and (co)oligomers and combinations thereof;and poly(vinyl acetate) as described above. This embodiment can befurther practiced including other embodiments disclosed above. Optionaladditives for Layer B include up to 1 wt % carbon black and high κnanoparticles with preferred high κ dielectric nanoparticles forpracticing this embodiment selected from the group: barium titanate,strontium titanate, barium strontium titanate and titanium dioxide.

Layer A and optional Layer B may include additives such as fillers,surfactants, defoamers, dispersants and grinding aids. Numeroussurfactants, defoamers, dispersants and grinding aids are available thatare suitable for this purpose. Selection will often be based uponobserved coating and dispersion quality and the desired adhesion of thedielectric layer to other layers in the thermal transfer process. Incertain embodiments, the surfactants comprise siloxy-, fluoryl-,alkyl-and alkynyl-substituted surfactants. These include the Byk® (BykChemie), Zonyl® (DuPont), Triton® (Dow), Surfynol® (Air Products) andDynol® (Air Products) surfactants. Preferred surfactants are Byk® 345,346 and 348 and Zonyl® FSO and FSN. In certain embodiments, thedefoamers comprise alkyl and alkynyl functionality and include Surfynol®defoamers. In certain embodiments, the disperants comprisefunctionalized polymers, oligomers and monomers and include Surfynol®and Disperbyk® dispersants.

The Tgs of the dielectric polymers utilized in Layer A and Layer B rangefrom about −30 to about 150° C., and preferably about 20 to about 90° C.and most preferably about 30 to about 70° C. Typically, the addition offillers enables the utilization of lower Tg polymers and the addition ofplasticizers enables the utilization of higher Tg polymers. Thepreferred Tg of the dielectric layer itself and of the layers utilizedin the dielectric layer, including Layer A and Layer B is about 30 toabout 100° C., preferably about 40 to about 85° C. and most preferablyabout 45 to about 65° C.

The preferred thickness of the dielectric layer and of the layersutilized in the dielectric layer, including Layer A and Layer B, isabout 0.05 to about 10 microns, preferably about 0.1 to about 5 microns,and more preferably about 0.2 to about 3 microns.

Another embodiment is a composition useful for preparing the dielectriclayer(s) of the invention comprising one or more dielectric polymer(s)and one or more near-IR dye(s) as described above for Layer A; wherein adry layer comprising said composition has a resistivity of 10¹⁴ ohm-cmor greater and has an absorption maximum in the region of about 600 toabout 1200 nm. In a related embodiment the composition of the inventionfurther comprises a high κ nanoparticle fraction up to 90 wt % based onthe dry weight of the composition, with the proviso that if thenanoparticle fraction is greater than 80 wt %, the near-IR dye is lessthan 6 wt % of the composition. In a preferred embodiment thecomposition consists essentially of one or more dielectric polymer(s)and one or more near-IR dye(s) as described above for Layer A. Inanother preferred embodiment the composition further consistsessentially of a high κ nanoparticle fraction up to 90 wt % based on thedry weight of the composition, with the proviso that if the nanoparticlefraction is greater than 80 wt %, the near-IR dye is less than 6 wt % ofthe composition.

Compositions useful for preparing the dielectric layer(s) can beprepared by dispersing and/or dissolving the dielectric polymer(s),near-IR dye(s) and, optionally, the high κ nanoparticle fraction, in asuitable volatile carrier fluid to provide a solution or suspension.Typically the volatile carrier fluid is water, an organic solvent, agaseous material, or some combination thereof. The volatile carrierfluid is chosen to be compatible with the various components of thecomposition. Examples of volatile carrier fluids include water, loweralcohols such as ethanol, aliphatic and aromatic hydrocarbons such ashexane, cyclohexane and xylenes; ethers such as dibutyl ether; etheralcohols such as 2-methoxyethanol; esters such as butyl acetate; andaliphatic and aromatic halocarbons such as 1,2-dichloroethane. Lowermolecular weight oligomers and small molecules useful as processing aidsincluding the dispersants and surfactants listed above may be present inthe compositions.

A dielectric layer can be made by coating a solution or suspension ontoa suitable substrate and removing the carrier fluid. Applying thesolution or suspension can be accomplished by any method that gives auniform layer, or if desired, a patterned or non-uniform layer. Coating,including rod-coating, extrusion coating, gravure coating andspin-coating, spraying, printing, blading or knifing can be used.Coating and spraying are preferred methods. Many commercial coatingmachines, devices such as a coating rod and knife blade, and printingmachines can be used to apply the solution or suspension. The carrierfluid is allowed to evaporate to provide the dielectric layer. Thedielectric layer can be dried by any conventional method of dryingincluding applying heat and vacuum.

Multilayer Thermal Imaging Donor

Another embodiment of the invention is a multilayer thermal imagingdonor comprising: a base film; and a dielectric transfer layercomprising at least one Layer A as described above, wherein thedielectric transfer layer is has a resistivity of 10¹⁴ ohm-cm orgreater. In various embodiments the thermal imaging donor may include:an LTHC layer interposed between the base film and the dielectrictransfer layer; an interlayer interposed between the base film and thedielectric transfer layer; and an interlayer interposed between an LTHClayer and the dielectric transfer layer. In another embodiment, thedielectric transfer layer may further comprise one or more additionaldielectric layer(s) comprising Layer B as described above. Theadditional dielectric layer(s) may be below and/or on top of Layer A.

The thermal imaging donor may optionally include other layers known inthe art, for example, an antistatic layer may be present adjacent thebase film and opposite the transfer layer; a primer layer, ejectionlayer, and/or an underlayer may be disposed between the base film andthe LTHC layer; and an adhesive layer may be disposed adjacent thedielectric transfer layer opposite the base film. Thus, one or moreother conventional thermal transfer donor element layers can be includedin the thermal imaging donor of the present invention, including but notlimited to an interlayer, primer layer, release layer, ejection layer,thermal insulating layer, underlayer, adhesive layer, humectant layer,and light attenuating layer.

FIG. 1A is a cross-sectional view of thermal imaging donor 100, inaccordance with one embodiment of the invention. Thermal imaging donor100 comprises a base film 102 and a dielectric transfer layer 106 on thesurface of the base film.

Base film 102 provides support to the other layers of thermal imagingdonor 100. Base film 102 comprises a flexible polymer film and ispreferably transparent. A suitable thickness for base film 102 is about25 μm to about 200 μm, although thicker or thinner support layers may beused. The base film may be stretched by standard processes known in theart for producing oriented films and one or more other layers, such asthe LTHC layer, may be coated onto the base film prior to completion ofthe stretching process. Preferred base films comprise a polymericmaterial selected from the group consisting of: polyethyleneterephthalate (PET), polyethylene naphthalate (PEN), triacetyl celluloseand polyimide with PET being especially preferred.

Light-Attenuating Agent

A light-attenuating agent may be present in a discrete layer orincorporated in one of the other functional layers of the donor element,such as the base film, the LTHC layer or the dielectric transfer layer.In one embodiment, the base film comprises a small amount (typically0.2% to 0.5% by weight of the base film) of a light-attenuating agentsuch as a dye which can assist in the focusing of the radiation sourceonto the radiation-absorber in the LTHC layer during the thermal imagingstep, thereby improving the efficiency of the transfer process. U.S.Pat. No. 6,645,681, incorporated herein by reference, describes this andother ways in which the base film may be modified to assist in thefocusing of a laser radiation source in which the equipment comprises animaging laser and a non-imaging laser wherein the non-imaging laser hasa light detector that is in communication with the imaging laser. Thewavelength ranges at which the imaging and non-imaging laser operate(typically in the range from about 300 nm to about 1500 nm) determinethe wavelength ranges in which the absorber(s) and/or diffuser(s) areactive and inactive. For example, if the non-imaging laser operates inabout the 670 nm region and the imaging laser at 830 nm, it is preferredthat the absorber and/or diffuser operate to absorb or diffuse light inthe 670 nm region, rather than in the 830 nm region. Herein, the lightattenuating agent preferably absorbs or diffuses light in the visibleregion, and in one embodiment absorbs around 670 nm. Suitablelight-attenuating agents are well known in the art and include thecommercially available Disperse Blue 60 and Solvent Green 28 dyes andcarbon black. Preferably the amount of light-attenuating agent issufficient to achieve an optical density (OD) of 0.1 or greater at somewavelength of about 400 to about 750 nm, more preferably about 0.3 toabout 1.5.

The light-attenuating agent of U.S. Pat. No. 6,645,681 referred toherein above may be incorporated into the dielectric transfer layerinstead of, or additionally to, the base film. The nature of thislight-attenuating agent will be dependent on the particular laser andprinting system that is utilized. Dyes useful as attenuating agents forpolymer-based dielectric layers include Oil Blue N and Methylene Blue.

Light to Heat Conversion Layer (LTHC)

The thermal imaging donor may, optionally, have alight-to-heat-conversion layer (LTHC) interposed between the base filmand the other layers. FIG. 1B is a cross-sectional view of thermalimaging donor 100, in accordance with another embodiment of theinvention. Thermal imaging donor 100 comprises a LTHC layer 108interposed between base film 102 and the dielectric transfer layer 106.

The LTHC layer 108 is incorporated as a part of thermal imaging donor100 for radiation-induced thermal transfer to couple the energy of lightradiated from a light-emitting source into the thermal transfer donor.

Typically, the radiation absorber in the LTHC layer (or other layers)absorbs light in the infrared, visible, and/or ultraviolet regions ofthe electromagnetic spectrum and converts the absorbed light into heat.The radiation absorber is typically highly absorptive, providing anoptical density (OD) at the wavelength of the imaging radiation of 0.1to 3 or higher, and preferably from 0.2 to 2.

Suitable radiation absorbing materials can include, for example, dyes(e.g., visible dyes, ultraviolet dyes, infrared dyes, fluorescent dyes,and radiation-polarizing dyes), pigments, metals, metal compounds, metalfilms, and other suitable absorbing materials. Suitable radiationabsorbers and binders for LTHC layers are well-known in the art andextensive lists and references can be found in PCT/US05/38010;PCT/US05/38009; U.S. Pat. No. 6,228,555 B1; Matsuoka, M., “InfraredAbsorbing Materials”, Plenum Press, New York, 1990; and Matsuoka, M.,Absorption Spectra of Dyes for Diode Lasers, Bunshin Publishing Co.,Tokyo, 1990; which are herein incorporated by reference. One example ofa suitable LTHC layer can include a pigment, such as carbon black, and abinder, such as an organic polymer. Preferred classes of near-infrareddyes are cyanine compounds selected from the group consisting of:indocyanines, phthalocyanines including polysubstituted phthalocyaninesand metal-containing phthalocyanines, and merocyanines.

Sources of suitable infrared-absorbing dyes include H. W. SandsCorporation (Jupiter, Fla., US), American Cyanamid Co. (Wayne, N.J.),Cytec Industries (West Paterson, N.J.), Glendale ProtectiveTechnologies, Inc. (Lakeland, Fla.) and Hampford Research Inc.(Stratford, Conn.). Preferred dyes for LTHC and transfer layers are3H-indolium,2-[2-[2-chloro-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)ethylidene]-1-cyclopenten-1-yl]ethenyl-1,3,3-trimethyl-,salt with trifluoromethanesulfonic acid (1:1) having CAS No.[128433-68-1], available from Hampford Research Inc, Stratford, Conn.,as TIC-5c,2-(2-(2-chloro-3-(2-(1,3-dihydro-1,1-dimethyl-3-(4-sulphobutyl)-2H-benz[e]indol-2-ylidene)ethylidene)-1-cyclohexene-1-yl)ethenyl)-1,1-dimethyl-3-(4-sulphobutyl)-1H-benz[e]indolium,inner salt, free acid having CAS No. [162411-28-1], available from H. W.Sands Corp, as SDA 4927; and indolenine dyes SDA 2860 and SDA 4733 fromH. W. Sands Corp. SDA 4927 is an especially preferred dye for the LTHClayer.

An LTHC layer may include a particulate radiation absorber in a binder.Examples of suitable pigments include carbon black and graphite.

The weight percent of the radiation absorber in the LTHC layer,excluding the solvent in the calculation of weight percent, is generallyfrom about 1 wt % to about 85 wt %, preferably from 3 wt % to 60 wt %,and most preferably from 5 wt % to 40 wt %, depending on the particularradiation absorber(s) and binder(s) used in the LTHC layer. Suitablebinders for use in the LTHC layer include film-forming polymers, suchas, for example, phenolic resins (e.g., novolak and resole resins),polyvinyl butyral resins, polyvinyl acetates, polyvinyl acetals,polyvinylidene chlorides, polyacrylates, and styrene acrylics. The %transmittance of the LTHC layer is affected by the identity and amountof the radiation absorber and the thickness of the LTHC layer. The LTHClayer should exhibit radiation transmission of about 20% to about 80%,more preferably of about 40% to about 50%, at the wavelength of theimaging radiation used in the thermal transfer imaging process. When abinder is present, the weight ratio of radiation absorber to binder isabout 5:1 to about 1:1000 by weight, preferably about 2:1 to about 1:100by weight. A polymeric or organic LTHC layer is coated to a thickness of0.05 μm to 20 μm, preferably, 0.05 μm to 10 μm, and, more preferably,0.1 μm to 5 μm.

In preferred embodiments, the LTHC layer is based upon a broad varietyof water-soluble or water-dispersible polymeric binders withcompositions as disclosed in the above referenced PCT/US05/38010 andPCT/US05/38009. Preferably, the average particle size of awater-dispersible binder in its aqueous phase is less than 0.1 micron,and more preferably less than 0.05 micron, and preferably having anarrow particle size distribution.

Preferred water-soluble or water-dispersible polymeric binders for LTHClayers useful in the invention are those selected from the group:acrylic resins and hydrophilic polyesters and more preferablysulphonated polyesters as described in the above referencedPCT/US05/38009. Other preferred polymeric binders for LTHC layers aremaleic anhydride polymers and copolymers including those comprisingfunctionality provided by treating the maleic anhydride polymers and/orcopolymers with alcohols, amines, and alkali metal hydroxides. Specificmaleic anhydride based copolymers comprise the structure represented byformula (III)

-   wherein x and z are any positive integer;-   wherein y is zero or any positive integer;-   R₂₁ and R₂₂ can be the same or different, and individually are    hydrogen, alkyl, aryl, aralkyl, cycloalkyl, and halogen, provided    that one of R₂₁ and R₂₂ is an aromatic group;-   R₃₁, R₃₂, R₄₁ and R₄₂ are the same or different groups, which can be    hydrogen or alkyl of one to about five carbon atoms; and-   R₅₀ is functional group selected from:

a) alkyl, aralkyl, alkyl-substituted aralkyl radicals containing fromone to about twenty carbon atoms;

b) oxyalkylated derivatives of alkyl, aralkyl, alkyl-substituted aralkylradicals containing from about two to about four carbon atoms in eachoxyalkylene group, which can be of one to about twenty repeating units;

c) oxyalkylated derivatives of alkyl, aralkyl, alkyl-substituted aralkylradicals containing from about two to about four carbon atoms in eachoxyalkylene group, which can be of one to about six repeating units;

d) at least one unsaturated moiety;

e) at least one heteroatom moiety;

f) alkaline molecules capable of forming salts selected from Li, Na, Kand NH₄ ⁺; and

g) combinations thereof.

A preferred maleic anhydride polymer for LTHC layers comprises acopolymer of formula (III), wherein R₂₁, R₃₁, R₃₂, R₃₃, R₄₁, R₄₂, R₄₃,are individually hydrogen, R₂₂ is phenyl, and R₅₀ is 2-(n-butoxy)ethyl.A specific example of a maleic anhydride copolymer useful in LTHC layersis a styrene maleic anhydride copolymer such as SMA 1440H, a product ofSartomer Corporation, Exton, Pa.

In one embodiment of the invention, a preferred LTHC layer comprises oneor more water-soluble or water-dispersible radiation-absorbing cyaninecompound(s) selected from the group consisting of: indocyanines,phthalocyanines including polysubstituted phthalocyanines andmetal-containing phthalocyanines, and merocyanines; and one or morewater-soluble or water-dispersible polymeric binders selected from thegroup consisting of: acrylic resins, hydrophilic polyesters, sulphonatedpolyesters, and maleic anhydride homopolymers and copolymers. A mostpreferred LTHC layer further comprises one or more release modifiersselected from the group consisting of: quaternary ammonium cationiccompounds; phosphate anionic compounds; phosphonate anionic compounds;compounds comprising from one to five ester groups and from two to tenhydroxyl groups; alkoxylated amine compounds; and combinations thereof.

Metal radiation absorbers also may be used as LTHC layers, either in theform of particles or as films, as disclosed in U.S. Pat. No. 5,256,506hereby incorporated by reference. Nickel and chromium are preferredmetals for the LTHC layer 108, with chromium being especially preferred.Any other suitable metal for the heating layer can be used. Thepreferred thickness of the heating layer depends on the opticalabsorption of the metals used. For chromium, nickel/vanadium alloy ornickel, a layer of 80-100 Angstroms is preferred.

Preferred radiation absorbers for LTHC layers utilized herein areselected from the group: metal films selected from Cr and Ni; carbonblack; graphite; and near infrared dyes with an absorption maxima in therange of about 600 to 1200 nm within the LTHC layer.

Interlayer

In one embodiment, the donor includes an interlayer (104) interposedbetween the base film and the dielectric transfer layer as shown in FIG.2A. Another donor includes an interlayer (104) interposed between theLTHC layer and the dielectric transfer layer as shown in FIG. 2B.Typical functions and requirements of the interlayer are described inU.S. Pat. No. 6,228,555 B1 together with materials suitable for use asinterlayers. The interlayer can be used, for example, to minimize damageand contamination of the transferred portion of the dielectric transferlayer. Preferred materials for the interlayer herein are thermosetpolymers selected from the group consisting of: crosslinked orcrosslinkable poly(meth)acrylates, polyesters, epoxies, andpolyurethanes; and thermoplastic polymers selected from the group:poly(meth)acrylates, polystyrenes, polyurethanes, polysulfones,polyesters, polyimides, and ethylene copolymers includingethylene-norbornene copolymers. It is preferred that the thermoplasticpolymers have a Tg greater than about 70° C., more preferably greaterthan about 100° C., and most preferably greater than about 130° C., anda M_(w) greater than about 50,000 and more preferably greater than about100,000. The thermoset polymers may be coated onto the LTHC layer as,for example, thermoplastic precursors and subsequently crosslinked toform a crosslinked interlayer. Preferred interlayers herein comprise athermoset polymer, or a thermoplastic polymer with a Tg greater thanabout 70° C., and are characterized by greater than 80% transmission inthe 600 nm to about 1200 nm wavelength region.

Multilayer Dielectric Transfer Layers and Cover Layers

In another preferred embodiment, the dielectric transfer layer comprisestwo or more Layers A that are gradient dye layers as described above.FIG. 3A illustrates this embodiment, wherein dielectric layers 106A and106B are gradient dye layers comprising different loadings of near-IRdye.

In another preferred donor of the invention, the dielectric transferlayer comprises two or more Layers A that are gradient nanoparticlelayers as described above. FIG. 3B, illustrates this embodiment whereindielectric layers 106C and 106D are gradient nanoparticle layerscomprising different loadings of nanoparticles.

In another preferred donor of the invention the dielectric transferlayer comprises two or more layers of Layers A that are gradient layerswith respect to both near-IR dye loading and high κ nanoparticlefraction, within the limits described above.

Another preferred donor of the invention, illustrated in FIG. 3C,includes a dielectric transfer layer comprising a Layer A 106A and oneor to more additional dielectric Layer(s) B 106E, comprising one or moredielectric polymer(s) having a resistivity of about 10¹⁴ ohm-cm orgreater.

The multilayer thermal imaging donor can be prepared by coatingrespective layers onto a suitable base film. A wide variety of coatingmethods can be used including those described above for preparation ofthe dielectric layers.

Optionally, a protective strippable cover layer may be present on theoutmost layer of the thermal transfer donor. The cover layer protectsthe underlaying transfer layers and is easily removable. A preferredcover sheet is polyethylene film.

Receivers and Imaging Process

The thermal transfer donors are useful in thermal transfer patterning ofone or more dielectric layer(s) onto a thermal imaging receiver toprovide a patterned dielectric layer(s) using a thermal transferprocess.

FIG. 4 is a cross-sectional view of a thermal imaging receiver 200 thatcomprises a receiver base film 202 and optional image receiving layer204. The receiver base film 202 comprises a dimensionally stable sheetmaterial as defined for the base film of the thermal imaging donor.Additionally, the receiver base film can be an opaque material, such aspolyethylene terephthalate filled with a white pigment such as titaniumdioxide; ivory paper; or synthetic paper, such as Tyvek® spunbondedpolyolefin. The sheet material can also be glass. Preferred base filmsfor receivers are polyethylene terephthalate, polyethylene naphthalate,polyimide, triacetyl cellulose, and glass._The optional image receivinglayer 204 facilitates adhesion of the thermal imaging receiver 200 tothe thermally imaged transfer layer 106. Suitable image receiving layers204 comprise a broad range of polymers including any of the(co)polymers/co(oligomers)/resins mentioned above in the description ofthe dielectric layer(s). Typical polymers for the receiver layer are(meth)acrylic polymers, including (meth)acrylate homopolymers andcopolymers, (meth)acrylate block copolymers, and (meth)acrylatecopolymers containing other comonomer types, such as styrene. Thereceiver element may optionally include one or more additional layersbetween the receiver support and the image receiving layer includingrelease layers, cushion layers and adhesive layers. Receiving elementssuitable for use herein are disclosed as transfer elements in U.S. Pat.No. 5,565,301 and as receiver elements in WO 03/099574, both of whichare hereby incorporated by reference. Alternate receiver elements aredisclosed in U.S. Pat. No. 5,534,387, hereby incorporated by reference.Preferred cushion layers herein are ethylene vinylacetate copolymers(Elvax® copolymers, DuPont). Methods of roughening the receiver surfaceare described in WO 03/009574. A preferred roughening method herein isto bring the receiver surface in contact with a roughened sheet,typically under pressure and heat.

The various embodiments of the thermal imaging donors are useful information of patterned dielectric layers for electronic devices such asdisplays and touchpads. To image the thermal imaging donor, the donor iscontacted with a thermal imaging receiver. By contacted is meant thatthe donor is in close proximity, preferably within several microns, ofthe receiver. In some embodiments, when contacted, there is nodetectable distance between the donor and receiver. The receiver may beoff-set from the donor by, for example, previously printed layers,fibers or particles that act as spacers to provide a controlled gapbetween donor and receiver. Vacuum and/or pressure can be used to holdthe donor element 100 and the receiver element 200 together. As onealternative, the donor element 100 and the receiver element 200 can beheld together by fusion of layers at the periphery of the assembly.

At least a portion of the one or more dielectric transfer layer(s) istransferred to the thermal imaging receiver by thermal transfer to forma patterned dielectric layer(s). Wherein the dielectric transfer layercomprises one or more additional dielectric layer(s), a correspondingproximate portion of the additional dielectric layer(s) is transferredin the transfer process. Preferably the thermal transfer is alaser-mediated transfer process. In one embodiment, the assembly of thedonor element 100 and the receiver element 200 is selectively exposed toheat, which is preferably in the form of laser radiation, in an exposurepattern of the image of the desired pattern to be formed on thesubstrate. The laser radiation is focused about at the LTHC layer, or ifthe LTHC layer is not present, at about the interface between thoselayers to be transferred and those to remain with the donor. Sufficientradiation is applied to achieve transfer of the desired transfer layersto the receiver.

A variety of light-emitting sources can be used to heat the thermaltransfer donor elements. For analog techniques (e.g., exposure through amask), high-powered light sources (e.g., xenon flash lamps and lasers)are useful. For digital imaging techniques, infrared, visible, andultraviolet lasers are particularly useful. Other light sources andirradiation conditions can be suitable based on, among other things, thedonor element construction, the transfer layer material, the mode ofthermal transfer, and other such factors.

The radiation is preferably applied through the backside of base film102, that is, the side opposite the dielectric transfer layer(s). Laserradiation is preferably provided at a laser fluence of up to about 600mJ/cm², more preferably about 75-440 mJ/cm². Lasers with an operatingwavelength of about 350 nm to about 1500 nm are preferred. Particularlyadvantageous are diode lasers, for example those emitting in the regionof about 750 to about 870 nm and up to 1200 nm. Such lasers areavailable from, for example, Spectra Diode Laboratories (San Jose,Calif.). One device used for applying an image to the receiver is theCreo Spectrum Trendsetter 3244F, which utilizes lasers emitting near 830nm. This device utilizes a Spatial Light Modulator to split and modulatethe 5-50 Watt output from the ˜830 nm laser diode array. Associatedoptics focus this light onto the imageable elements. This produces 0.1to 30 Watts of imaging light on the donor element, focused to an arrayof 50 to 240 individual beams, each with 10-200 mW of light inapproximately 10×10 to 2×10 micron spots. Similar exposure can beobtained with individual lasers per spot, such as disclosed in U.S. Pat.No. 4,743,091. In this case each laser emits 50-300 mW of electricallymodulated light at 780-870 nm. Other options include fiber-coupledlasers emitting 500-3000 mW and each individually modulated and focusedon the media. Such a laser can be obtained from Opto Power in Tucson,Ariz.

Suitable lasers for thermal imaging include, for example, high power(>90 mW) single mode laser diodes, fiber-coupled laser diodes, anddiode-pumped solid state lasers (e.g., Nd:YAG and Nd:YLF). Laserexposure dwell times can vary widely from, for example, a few hundredthsof is microseconds to tens of microseconds or more, and laser fluencescan be in the range from, for example, about 0.01 to about 5 J/cm² ormore.

After exposure, the donor element 100 and the receiver element 200 areseparated, as illustrated in FIGS. 5A and 5B, leaving the untransferredportions of the dielectric layer 106 on the donor element 100 and thepatterned dielectric layer on the receiver element 200. Usually theseparation of the donor and receiver is achieved by simply peeling thetwo elements apart. This generally requires very little peel force andis accomplished by simply separating the donor element from the receiverelement. This can be done using any conventional separation techniqueand can be manual or automatic.

In some instances, depending upon the nature of the donor and receiverelements and the transfer processing parameters, when the donor elementand the receiver element are separated after thermal transfer, thereceiver element includes both exposed portions and some non-exposedportions of one or more transfer layers. A useful process for enhancingthe resolution of a thermally transferred pattern on a thermal transferreceiver, wherein the thermal transfer receiver comprises a surfacehaving an exposed portion and a non-exposed portion, of one or morethermally transferred layers, comprises: (a) contacting the surface withan adhesive layer for a contact period to provide a laminate; (b)separating said adhesive layer from the laminate to provide a treatedthermal transfer receiver having a surface substantially free of saidnon-exposed portion of one or more thermally transferred layers.

Non-exposed portions of one or more thermally transferred layers can bein the form peel defects, defined herein as non-exposed portions of animaged layer that are transferred onto the receiver along with theexposed portion of the layer. These peel defects are typicallyrelatively weakly adhered to the receiver as compared to the exposedportions of the image. Minimization and absence of these peel defectscan be achieved by optimization of donor formulations, tuning of donordrying times and temperatures, control of the temperature and relativehumidity of the printing room, and by selection of the receiver andtuning of its surface through various surface treatments. The peeldefects can often be selectively removed by brief contact with anadhesive surface. Contact periods are about from 0.01 seconds tominutes, preferably 1 second to 10 minutes, more preferably 1-90seconds. Preferred adhesive surfaces include polymer- and metal-coatedsurfaces. Examples of such adhesive surfaces are Scotch® tape (3MCompany), a tacky roller such as a medium tack Dust Removal System-1roller (Systems Division, Inc., Irvine Calif.), the dielectric donor andreceiver substrates reported herein, most preferably the acryliclatex-based donor and receiver substrates, and the LTHC layer donorsubstrates reported herein, preferably the metallized LTHC donorsubstrates.

Either or both of the spent donor element (a negative of the image) andthe imaged receiver element (a positive of the image) may be useful as afunctional object. Furthermore, either or both of the spent donorelement and the imaged receiver element may be utilized as the permanentsubstrate or the image may be transferred from the spent donor orreceiver, preferably by lamination, to the permanent substrate. Thedonors of the invention can be used to prepare patterned dielectriclayers characterized by a resistivity of 10¹⁴ ohm-cm or greater.

Various electrical elements that can be formed, at least in part, by theuse of the present invention include electronic circuitry, resistors,capacitors, diodes, rectifiers, electroluminescent lamps, memoryelements, field effect transistors, bipolar transistors, unijunctiontransistors, thin film transistors, metal-insulator-semiconductorstacks, organic transistors, charge coupled devices,insulator-metal-insulator stacks, organic conductor-metal-organicconductor stacks, integrated circuits, photodetectors, lasers, lenses,waveguides, gratings, holographic elements, filters (e.g., add-dropfilters, gain-flattening filters, cut-off filters, and the like),splitters, couplers, combiners, modulators, sensors (e.g., evanescentsensors, phase modulation sensors, interferometric sensors, and thelike), optical cavities, piezo-electric devices, ferroelectric devices,thin film batteries, or combinations thereof; for example, thecombination of field effect transistors and organic electroluminescentlamps as an active matrix array for an optical display.

Materials

Unless otherwise indicated, chemicals were used as received withoutfurther purification. Solvents were purchased from Aldrich and VWR andwere of reagent-grade purity or higher; HPLC grade and preferablyelectronic grade solvents were used when available. Water was deionizedwater, HPLC grade water from Aldrich, or purified water. Polymers,plasticizers, IR dyes, and surfactants were obtained from the sourceslisted in the specification or purchased from Aldrich. Pigments such ascarbon black dispersions were obtained from Penn Color, Inc.,Doylestown, Pa. All raw polyester films were obtained from DuPont TeijinFilms (Wilmington, Del.). Silver nanoparticles were purchased from FerroCo.—Electronic Material Systems; Nanostructured & Amorphous Materials,Inc., and Mitsui Co. HiPco raw carbon nanotubes were purchased formCarbon Nanotechnologies, Inc., Houston Tex. Kapton HN was obtained fromDuPont De Nemours, Inc. (Circleville, Ohio). WPTS® 3737 (Water-ProofTransfer Sheet) was obtained from DuPont De Nemours, Inc. (Towanda,Pa.). Strontium titanate, barium titanate, and barium-strontium titanatenanoparticles (˜50 nm) were purchased from Aldrich (Milwaukee, Wis.),TPL (Albuquerque, N.Mex.), and Cabot Corporation (Boston, Mass.).

Coating

Coating of transfer and other layers onto donor and receiver elementswas carried out utilizing stainless steel wrapped and formed 0.5 inchdiameter coating rods purchased from R.D. Specialties, Inc. (RDS;Webster, N.Y.) and chrome-plated stainless steel formed 0.625 inchdiameter rods with a CN profile purchased from Buschman Corporation(Cleveland, Ohio). The free surface of the donor was cleaned with apressurized nitrogen stream immediately prior to coating to rid thesurface of particle contamination. The coatings were drawn by hand onthe donor mounted on a smooth glass surface or machine-coated utilizinga WaterProof® Color Versatility coating system (CV coater) manufacturedby DuPont De Nemours Inc. (Wilmington, Del.).

Coatings were stored in a controlled temperature/humidity environmentwith an average temperature of about 68° C. and about 40-50% averagerelative humidity.

Donor Substrates

Cr LTHC Layer. A base film of polyethylene terephthalate (PET, 50microns thick in all examples unless stated otherwise) was coated withchrome metal in a vacuum deposition chamber. Metallization was carriedout on PET films with and without light attenuating agents (670 nmabsorbers). The chrome layer was coated at both 50% T and 40% T. In theexamples, these donor films will be referred to as: 40% T Cr PET donorsubstrate and as 50% T Cr PET donor substrate; for the metallized filmswithout light attenuating agents. The donor films with 670 nm absorbersincorporated in the base film will be referred to as: 40% T Cr Blue PETdonor substrate and as 50% T Cr Blue PET donor substrate.

Ni LTHC Layer. A process similar to that given for Cr above was carriedout for preparing donors with 50% T Ni LTHC layers. Instead ofincorporating a light-attenuating agent in the base film, a 1% solutionof Methylene Blue (MB; Aldrich) in methanol was coated on the back-sideof the donor substrate (the side opposite the LTHC layer) according tothe following procedure: The 50% T Ni PET donor substrate (20 cm by 30cm) was placed on a flat sheet of glass with the LTHC layer facing down.The methylene blue solution (˜3 mL) was dispensed from a syringe througha 0.45 micron pore-size filter along one short edge of the donor. Usinga #4 formed stainless steel RDS coating rod, the bead of solution washand-drawn into a thin film covering the back-side of the thermalimaging substrate. The film was air-dried. This donor substrate will bereferred to herein as 50% T Ni PET-MB donor substrate.

Organic LTHC Layer. The organic LTHC layer was prepared as reported inFormulation L of the Examples of PCT/US05/38009:

A LTHC coating formulation was prepared from the following materials:(i) demineralized water: 894 g; (ii) dimethylaminoethanol: 5 g; (iii)Hampford dye 822 (Hampford Research; formula corresponds to SDA 4927):10 g; (iv) polyester binder (Amertech Polyester Clear; American Inks andCoatings Corp; Valley Forge; PA): 65 g of a 30% aqueous solution; (v)TegoWet™ 251(4) (a polyether modified polysiloxane copolymer,Goldschmidt): 2.5 g; (vi) potassium dimethylaminoethanol ethylphosphate: 14 g of an 11.5% aqueous solution [The 11.5% aqueous solutionwas prepared by combining three parts water and 0.5 parts ethyl acidphosphate (Stauffer Chemical Company, Westport, Conn.: Lubrizol,Wickliffe, Ohio) and sufficient 45% aqueous potassium hydroxide toachieve a pH of 4.5, followed by addition of sufficientdimethylaminoethanol to achieve a pH of 7.5 and finally dilution withwater to achieve five parts total of final aqueous solution of 11.5relative mass percent of water-free compound.]; (vii) crosslinker Cymel™350 (a highly methylated, monomeric melamine formaldehyde resin, CytecIndustries Inc., West Paterson, N.J.): 10 g of a 20% solution; and(viii) ammonium p-toluene sulphonic acid: 2 g of a 10% aqueous solution.

Ingredients (ii) and (iii) were added to the water and allowed to stirfor up to 24 hours before addition of the other ingredients in the ordershown. The formulation was applied in an in-line coating technique asfollows: The polymer base film composition was melt-extruded, cast ontoa cooled rotating drum and stretched in the direction of extrusion toapproximately 3 times its original dimensions at a temperature of 75° C.The cooled stretched film was then coated on one side with the LTHCcoating composition to give a wet coating thickness of approximately 20to 30 μm. A direct gravure coating system was used to apply the coatingsto the film web. A 60QCH gravure roll (supplied by Pamarco) rotatedthrough the solution, taking solution onto the gravure roll surface. Thegravure roll rotated in the opposite direction to the film web andapplied the coating to the web at one point of contact. The coated filmwas passed into a stenter oven at a temperature of 100-110° C. where thefilm was dried and stretched in the sideways direction to approximately3 times its original dimensions. The biaxially stretched coated film washeat-set at a temperature of about 190° C. by conventional means. Thecoated polyester film was then wound onto a roll. The total thickness ofthe final film was 50 microns; the dry thickness of the LTHC layer was0.07 microns. The PET support layer contained either Disperse Blue 60 orSolvent Green 28 dye to give a final dye concentration of typically 0.2%to 0.5% by weight in the polymer of the substrate layer. The polymercomposition containing the Disperse Blue 60 dye (0.26% by weight) had anabsorbance of 0.6±0.1 at 670 nm, and an absorbance of <0.08 at 830 nm.The polymer composition containing the Solvent Green 28 dye (0.40% byweight) had an absorbance of 1.2 at 670 nm, and an absorbance of <0.08at 830 nm. These donor substrates will herein be referred to as: OrganicLTHC Blue PET donor substrate and Organic LTHC Green PET donorsubstrate.

WPTS®: WaterProof® Transfer Sheet (WPTS® 3737; DuPont, Towanda) was usedas the donor substrate for laminations. Immediately prior to coating onthis substrate, the polyethylene coversheet was removed to expose therelease layer of the WPTS® sheet. The coating was applied on thisrelease layer.

Dielectric Measurements

Dielectric electrical properties were tested by spin-coatingsolvent-based dielectrics or laminating (unless spin-coating isspecified) aqueous-based dielectrics from WPTS® onto a glass substratepre-patterned with ten aluminum “fingers”. A top aluminum electrode wasthen evaporated over the central portion of the substrate to form tensmall capacitor structures. Alternatively, if “ITO Method” is specified,the dielectric was rod-coated on the ITO sputtered surface of a PETsubstrate [700 mil Melinex® ST504 film (DuPont Teijin Films) with ITOsputtered on the non-treated side by Courtalds with 0050 (50ohm/square)] using a Buschman 7CN rod and a CV coater, and ten aluminumfingers were evaporated onto the free surface of the dielectric.

The dielectric constant was determined by measuring the complexadmittance from 40 Hz to 110 MHz with an Agilent 4294 impedance bridge.The bulk resistivity was measured by applying a small dc voltage acrossthe device (typically <5 V) and measuring the current through the filmwith a sensitive preamplifier. Care was taken to confine the measurementto the linear part of the I-V curve before space charge limited currentsdominate.

Transistor Electrical Characterization

Transistor electrical performance was measured in air at roomtemperature using common techniques, for example as shown in S. M. Sze,Physics of Semiconductor Devices, page 442, John Wiley and Sons, NewYork, 1981. A Cascade MicroTech (Beaverton, Oreg.) probestation modelAlessi REL-6100 and a semiconductor parameter analyzer AgilentTechnologies (Palo Alto, Calif.) model 4155C were used to obtain currentversus gate voltage sweeps at constant drain voltage. Typically, gatevoltage was swept from +30 to −50 V with a constant source-to-drain biasof −50 V. A plot of square root of current versus gate voltage, atconstant drain voltage, was used to determine the saturation mobility.The slope of the straight line portion of the plot was used to definethe transconductance. From the transconductance, the device width andlength, and the specific dielectric capacitance, the transistorsaturation mobility was calculated.

Thermal Imaging Equipment and Donor Mounting

Creo Trendsetter® 800 was utilized. The Creo Trendsetter® 800 was amodified drum-type imager utilizing a modified Thermal 1.7 Head with a12.5 watt maximum average operating power at a wavelength of 830 nm with5080 dpi resolution. The 800 Trendsetter® was operated in a controlledtemperature/humidity environment with an average temperature of ˜68° C.and an average relative humidity of ˜40-50%. For each printingexperiment, a section of thermal imaging receiver was positioned on thedrum. The thermal imaging donor was loaded so that the side of the donorelement coated with the transfer layer was facing the free side of thereceiver. Imaging assemblages were exposed from the back side throughthe donor film base. Films were mounted using vacuum hold down to astandard plastic or metal carrier plate clamped mechanically to thedrum. In some experiments utilizing the Creo Trendsetter® 800, anonstandard ‘drum with vacuum holes machined directly onto the drum tomatch common donor and receiver sizes was used as a replacement for thestandard drum/carrier plate assemblage. Contact between the donor andreceiver was established by ˜600 mm of Hg vacuum pressure. Laser outputwas under computer control to build up the desired image pattern. Laserpower and drum speed were controllable and were adjusted in an iterativefashion to optimize image quality as judged by visual inspection of thetransferred image on the receiving surface.

Latex Binder Preparation

Latex binders that were used in the preparation of certain donor andreceiver elements were prepared according to the procedures of WO03/099574 with the materials reported in Table 1. Compositions arereported in Table 2 and were characterized by the analytical methodsreported in WO 03/099574. Monomers and initiators were commerciallyavailable (Aldrich Chemical Co., Milwaukee, Wis.) and used as received.The surfactant was Polystep® B-7, a 29 wt % solution of ammonium laurylsulphate in water (Stepan Co., Northfield, Ill.).

Chain Transfer Agent: This material was prepared as described in U.S.Pat. No. 5,362,826, Berge, et. al.: A 500 liter reactor was equippedwith a reflux condenser and nitrogen atmosphere. The reactor was chargedwith methyl ethyl ketone (42.5 kg) andisopropyl-bis(borondifluorodimethylglyoximato) cobaltate (III) (Co IIIDMG) (104 g) and the contents brought to reflux. A mixture of Co Ill DMG(26.0 g), methyl methacrylate (260 kg), and methyl ethyl ketone (10.6kg) was added to the reactor over a period of 4 hours. Starting at thesame time, a mixture of Vazo 67® (DuPont, 5.21 kg) and methyl ethylketone (53.1 kg) was added to the reactor over a period of 5 hours.After the additions, the reactor contents were kept at reflux foranother ½ hour. After cooling, this yielded 372 kg of a 70 wt % solutionof Chain Transfer Agent (a chain transfer agent solution), which wasused directly in the polymerizations.

TABLE 1 Materials for the Synthesis of Acrylic Latex Resins AcrylicLatex Resin LL-3- LH-3- LH-10- Reagent (grams) LH-3 LL-3 LH-1 LL-1 LH-0LL-0 LHEA-6 2GA 2GA 2GA Polystep B-7 6.90 6.90 6.90 6.90 6.90 6.90 6.906.90 6.90 6.90 Ammonium 0.40 0.20 0.20 0.20 0.40 0.20 0.20 0.40 0.400.40 Persulfate Methyl Methacrylate 252.0 228.0 260.0 236.0 264.0 240.0240.0 220.0 280.0 192.0 Butyl Acrylate 120.0 160.0 120.0 160.0 120.0160.0 120.0 160.0 100.0 100.0 Methacrylic Acid 12.00 12.00 4.00 4.00 0 00 12.00 12.00 40.00 Glycidyl 0 0 0 0 0 0 0 8.00 8.00 8.00 MethacrylateHEMA 0 0 0 0 0 0 24 0 0 0 Chain Transfer Soln 16.0 0 16.0 0 16.0 0 16.00 0 0 HEMA: 2-Hydroxyethyl Methacrylate.

TABLE 2 Composition and Analytical Data for Latex Resins Chain ParticleTransfer Diameter Tg Mn/ Mw/ Resin Solids Soln MMA BA MAA HEMA GMA (nm)(° C.) 1000 1000 LH-3 32.6 4 63 30 3 75 56 57 135 LL-3 33.3 0 57 40 3 9333 244 1399 LH-1 33.5 4 65 30 1 78 53 57 138 LL-1 33.4 0 59 40 1 93 34235 1539 LH-0 32.8 4 66 30 0 70 53 53 145 LL-0 33.4 0 60 40 0 92 34 69341 LHEA-6 32.6 4 60 30 0 6 71 50 57 150 LL-3-2GA 33.4 0 55 40 3 2 94 39LH-3-2GA 33.5 0 70 25 3 2 92 72 LH-10-2GA 33.5 0 48 40 10 2 86 59 MMA:Methyl Methacrylate; BA: Butyl Acrylate; MAA: Methacrylic Acid; HEMA:2-Hydroxyethyl Methacrylate; GMA: Glycidyl Methacrylate.

Receivers

Kapton® HN (5 mil; E.I. duPont de Nemours Co.) substrate was cleanedprior to use as a receiver by rinsing with methanol, wiping with aparticle free cloth, and blowing off with a dry nitrogen stream.Surface-treated 5 mil Melinex® ST504 (DuPont Teijin Films) was used asreceived.

R-1, R-2 and R-3 PET receivers with an acrylic latex image receivinglayer were prepared according to the procedure of WO 03/099574 (FlexibleReceiver FR-1 Procedure) by slot-die coating an acrylic latex polymerdispersion with Zonyl® FSA as the surfactant onto 4 mil Melinex® 574base film (DuPont-Teijin Films) or onto 4 mil Cronar®471X (DuPont-TeijinFilms) with an Elvax® 550 (ethylene vinyl acetate copolymer, DuPont)release layer between the acrylic image receiving layer and the Cronar®base film (Cronar®/Elvax®: WPTS®, DuPont). The preparation andcompositions of the acrylic latex polymers are described above, and thereceiver compositions are reported in Table 3.

TABLE 3 Receiver Material Receiver R-1 R-2 R-3 LH-3-2GA 2173 g 2607.6 —(33% Solids) LL-3-2GA 3259 g 3910.8 — (33% Solids) LH-10-2GA — — 12574.0(33% Solids) N,N-Dimethylethanolamine  75.0 g 90.0 109.6 (10% in water)Water (distilled) 8713 g 10455.6 221868.0 Zonyl FSA  30.0 g 36.0 43.2Butyl Cellosolve  750 g 900.0 1106.0 % Solids 12% 12% 11.6% CoatingWeight 13 mg/dm2 12.9 mg/dm2 Receiver 4 mil Melinex ® 574 1.25 milElvax ® 550/ 2.5 mil Elvax ® 550/ Cronar ® 471X Cronar ® 471XPolyethylene Cover Sheet No Yes Yes

General Procedure for the Preparation of Aqueous Dielectric Layers

A water solution was prepared by combining the specified amounts ofwater and, optionally, a 3 wt % ammonium hydroxide solution. Next, theIR dye, one-fourth of the water solution, and optional defoamers,surfactants and plasticizers were combined in a brown glass containerand mixed well. The optional second binder was weighed in a containertogether with one-fourth of the water solution and mixed well. Optionalfiller(s) (e.g., carbon black, high κ nanoparticles) were weighed inanother container with one-fourth of the water solution and mixed well.The binder was weighed in a large container with a stir bar and anyremaining water solution was added. The contents of the second binderdispersion, the IR dye dispersion, and the filler dispersion were slowlyadded to the stirring binder. After stirring for at least 15 additionalminutes, the formulation was filtered into a brown or foiled-coatedcontainer. The solution was filtered for a second time as it wassyringed across the end of a donor sheet and was then coated. Unlessspecified otherwise, filtrations were carried out with 0.45 micron poresize syringe filters (25 mm GD/X Glass Microfiber is GMF filter WhatmanInc., Clifton, N.J.), and coatings were carried out using a CV coaterwith a Buschman Rod 7CN at 9.8 ft/min. Typically, 17.95 total wt %solids solutions were utilized to give films with a thickness of ˜2.3microns.

General Procedure for the Preparation of Solvent-Based Dielectrics

The specified amounts of polymer, IR dye, plasticizer, solvents andother additives were weighed together in a brown vial. The vial was thencapped with a lid and shaken vigorously on a mechanical shaker for 3 to24 h. The solution was then filtered into a brown vial. The solution wasfiltered for a second time as it was syringed onto the edge of a donorsheet and was then coated. Unless specified otherwise, filtrations werecarried out with 0.45 micron pore size syringe filters (25 mm GD/X GlassMicrofiber GMF filter), and coatings were carried out using a CV coaterwith a Buschman Rod 7CN at 9.8 ft/min.

Formulation and Coating of Pani-DNNSA-CNT Donors

Pani-3%-#12: (3% HiPco CNT, Pani-DNNSA) A mixture of HiPco Raw CNT(0.0450 g), xylenes (19.680 g) and PANI-DNNSA [5.333 g, 27.30% by wt. inxylenes and 2-butoxyethanol (4:1 ratio) with 0.7 acid doping,synthesized according to U.S. Pat. No. 5,863,465] was treated in a rtwater sonication bath for 1 h. Then the mixture was placed in a 45° C.water bath for 5 min. After equilibration of the temperature, themixture was treated with a sonication probe (Dukane Co. Model 40TP200,Transducer Model 41C28) for 3 min, during which time the mixture wasstirred gently with a spatula at one-minute intervals. The dispersion(2.3 mL) was hand-coated onto a 40% T Cr PET donor substrate (˜30 cm×20cm) with a #12 formed Buschman rod, dried at it and then further driedat 70° C.

Pani-3%-#14: The above procedure was followed except using a #14 rod.

Pani-7%: (7% HiPco CNT, Pani-DNNSA) A mixture of HiPco Raw CNT (0.1225g), Disperbyk® 163 (0.066 g, BYK Chemie) and xylenes (27.612 g) wastreated in a it water bath with a sonication probe (Dukane Co. Model40TP200, Transducer Model 41C28) for 10 min, during which time themixture was stirred gently with a spatula at 5 min intervals. ThenPANI-DNNSA [7.327 g, 24.23% by wt. in xylenes and 2-butoxyethanol (4:1ratio) with 0.7 acid doping, synthesized according to U.S. Pat. No.5,863,465] was added into the mixture, and the mixture was placed in a45° C. water bath for 5 min. After equilibration of the temperature, themixture was treated with sonication for 5 min, during which time themixture was stirred gently with a spatula at one-minute intervals. Theresulting dispersion was filtered through a 1.0 micron Nitex® 03-1/1nylon screen (mesh count 690×470, pore size: 1 micron; Sefar AmericaInc., Depew, N.Y.). Into the filtrate was added 28.8 micro-L of a 10 wt% solution of Triton® X-114 in xylenes. The dispersion (13 mL) wascoated onto a 40% T Cr PET donor substrate using a CV coater at 5.8ft/min with a #10 CN formed Buschman rod and dried at 40° C. for 15 min.

Modified Pani-7% (mPani-7%): The following CNT-PANI donors were preparedaccording to the procedure for Pani-7%, except that a mixed solventsystem [1,2-dichlorobenzene (DCB) and xylenes] was used: mPani-7%-a: 10%DCB; mPani-7%-b: 20% DCB; mPani-7%-c: 30% DCB.

Formulation and Coating of Silver Donors

Aq/Elv-#8: (87.5% NAM 0471 CD Ag with Elvacite® 2028) A mixture ofO471CD Ag powder (10.497 g), a 20 wt % solution of Elvacite® 2028 inxylenes (7.512 g), and xylenes (12.006 g) was treated in a water bathwith sonication for 1 h, during which time the mixture was stirred witha spatula at 0.5-h intervals. The mixture was then treated in a rt waterbath with probe sonication for an additional 10 min, during which timethe mixture was stirred gently with a spatula at 5-min intervals. Theresulting dispersion was filtered with a 12 micron stainless screen(Twill Dutch Weave, mesh count 200×1400, absolute rating: 12-14 microns;Sefar America, Inc., Depew, N.Y.). The dispersion (10 mL) was coatedonto a 40% T PET donor substrate using a CV coater at 5.8 ft/min using a#8 formed Buschman rod and dried at 33° C. for 15 min.

Aq/Elv-CN6: Above procedure was followed except using CN6 rod.

Aq/Elv-CN7: Above procedure was followed except using a CN7 rod.

Aq/Elv-CN8: Above procedure was followed except using a CN8 rod.

mAg/Elv-CN8: Above procedure was followed except using a CN8 rod and amodified solvent mixture of 50% DCB and 50% xylenes.

mAq/Elv-CN7: Above procedure was followed except using a CN7 rod andmodified (longer) dispersion times: an extra 15 min before and an extra5 min at the end of the sonication bath.

Aq/Elv/CNT-#8: (1% CNT and 87.5% Ag NAM O471 CD with Elvacite® 2028) Amixture of CNT (HiPco R0447, 0.0121 g), 1,2-dichlorobenzene (6.030 g)and xylenes (6.019 g) were dispersed with probe sonication for 15 min,during which time the mixture was stirred with a spatula at 5 minintervals. Next, NAM O471CD Ag powder (10.503 g) and a 20 wt % solutionof Elvacite® 2028 in xylenes (7.513 g) were added to the mixture, andthe mixture was treated in a water bath with sonication for 1 h, duringwhich time the mixture was stirred with a spatula at 0.5-h intervals.The mixture was then dispersed in a rt water bath with probe sonicationfor an additional 10 min, during which time the mixture was stirredgently with a spatula at 5-min intervals. The resulting dispersion wasfiltered with a 12 micron stainless screen (Twill Dutch Weave, meshcount 200×1400, absolute rating: 12-14 microns; Sefar America, Inc.,Depew, N.Y.). The dispersion (10 mL) was coated onto a 40% T PET donorsubstrate using a CV coater at 5.8 ft/min with #8 formed Bushman rod anddried at 38° C. for 25 min.

mAq/Elv/CNT-#8: The above procedure was followed with the followingexceptions: A shot CNT from NAM was used and the coating was preparedwith a CN#8 rod and dried for 30 min.

General Procedure for Semiconductor Evaporation

Shadow masks were fabricated from 2-4 mil thick nickel foil. Shadow maskalignment to the printed array was done by hand, using a light table andstereomicroscope. Careful manipulation of the printed array relative tothe shadow mask allowed ˜50 micron alignment over 6 inch arrays withminimal damage to the printed array. Once aligned, magnets were used topinch the printed array and nickel shadow mask together and this wasthen reinforced with Kapton tape. Finally, the aligned mask/printedarray was carefully rolled onto a vacuum deposition drum in a KurtLesker Evaporator and loaded for semiconductor evaporation.Semiconductor was deposited by sublimation under vacuum (<3×10⁻⁷ Torr)onto the free surface. The semiconductor was deposited with an initialrate of 0.1 Å/s up to 60 Å, and then at 0.5 Å/s until the desiredthickness, typically 450 Å, was obtained, as determined by measurementwith a quartz crystal microbalance. This procedure was carried out withpentacene and semiconductors SC-H1 and SC-H2.

General Procedure for Printing a Bottom-Gate Transistor Array withAssociated Capacitors and Bus Lines

The above general procedure for printing and mounting with a CreoTrendsetter® 800 (Creo/Kodak, Vancouver, Canada) thermal platesetter wasfollowed for all printed layers. First, the receiver was loaded onto thedrum along with the gate (first layer) donor. Following printing, thegate donor was peeled away from the receiver to give a receiver with apatterned gate layer consisting of patterns of gate electrodes,capacitor electrodes, bus lines and test pads. Next, the dielectricdonor was loaded onto the drum, printed, and peeled away from thereceiver to give a receiver with consecutively patterned gate anddielectric layers. The dielectric layer was either patterned or printedas a solid block. Next, the source-drain donor was loaded onto the drum,printed, and peeled away from the receiver to give a receiver withpatterned gate, dielectric and source-drain layers. The source-drainlayer consisted of patterns of source-drain electrodes, capacitorelectrodes, bus lines and test pads.

Multilayer printed transistor arrays were designed using a standardphotolithography software package (L-Edit) and then converted to asingle postscript file for each layer. Each postscript file was thenused for layer-by-layer printing in the Trendsetter. Three patterns wereutilized in these examples with both solid and patterned dielectrics:(1) TFT Pattern 1: 150×15 micron source-drain channel; (2) TFT Pattern2: 600×50 micron source-drain channel; and (3) TFT Pattern 3: 1350×50micron source-drain channel. Next, the semiconductor was evaporatedthrough a mask in the source-drain channel region according to thegeneral procedure given above. The entire source-drain channel andsurrounding region was covered with a rectangular patch of semiconductorin the case of Patterns 1 and 3. In the case of Pattern 2, a 450×400micron patch of semiconductor was deposited in the channel region, togive a transistor with an effective channel of 450×50 microns.

Examples 1-19 PHS, PVA and Phenol-Aldehyde Dielectrics

Dielectric layers comprising poly(hydroxystyrene) [PHS], PHS copolymers,polyvinyl acetate) [PVA] and phenol-aldehyde polymers [Novolac® resins]with resistivities greater than 10¹⁴ ohm-cm were prepared from thecomponents reported in Tables A and B using the general procedure forsolvent-based dielectrics given above, and the thermal transfer of someof these dielectric layers is reported in Table C.

Donor Element Fabrication: The thermal imaging donor substrate (30 cm by20 cm; either 50% T Cr Blue PET or 50% T Ni PET-MB) was placed on a flatsheet of glass with the LTHC layer facing up. The dielectric solution (5mL) was dispensed from a syringe through a 0.45 micron pore-size filteralong one short edge of the donor (25 mm GD/X Glass Microfiber GMF,Whatman Inc.). Using a #7 formed stainless steel RDS coating rod, thebead of solution was hand-drawn into a uniform thin film covering theLTHC layer of the thermal imaging substrate. The film was air-dried,resulting in a dielectric layer on top of the LTHC layer.

Pani/CNT/DNNSA: In the case of Examples 13 and 17, a receiver patternedwith PANI/CNT/DNNSA stripes was utilized in order to test patterning andadhesion of the dielectric layer onto both the receiver surface and thePANI/CNT/DNNSA conductor surface. The power series of solid blockpatterns for the dielectric layers of Examples 13 and 17 were printed ina row on top of these stripes.

Thermal Transfer Process for Conductor Stripes: Pani-3%-#12 andPani-3%-#14 donors were used in Examples 13 and 17, respectively. Aportion of the pani donor and a thermal imaging receiver (˜28 cm×18 cm)were loaded into the Creo Trendsetter® 800 thermal platesetter accordingto the general procedure described above. Seven evenly spaced patternswere printed on the receiver, with each pattern consisting of fourhorizontal stripes with 13 cm length, 1000 micron width and 1500 micronspacing between the stripes. For Example 13, printing parameters for allpatterns were as follows: drum speed=200; surface depth=70; surfacereflectivity=0.44; escan=1; 2× hit at 5.25 W. For Example 17, printingparameters for all patterns were as follows: drum speed=170; surfacedepth=78; surface reflectivity=0.46; escan=1; 2× hit at 5 W.

Thermal Transfer Process for Dielectric Layer: A portion of thedielectric donor and a thermal imaging receiver (˜28 cm×18 cm) were isloaded into the Creo Trendsetter® 800 thermal platesetter according tothe general procedure described above. (In the case of Examples 13 and17, the patterned receiver was left in place on the drum after removingthe pani donor. The dielectric donor was then loaded.) Solid blockpatterns were printed using the printing parameters given in Table C.The size of the solid block patterns varied from 2.5 cm×1.25 cm to 2.5cm×0.8 cm.

TABLE A PHS and PVA Dielectric Layer Compositions and ElectricalProperties Dielectric Other Constant Polymer IR Dye PlasticizerAdditives (at 10³ Hz) Amount Amount Amount Amount Solvent ResistivityEx. Wt % Wt % Wt % Wt % Amount Ohm-cm  1 PHS-B Tic-5cAcetone/Cyclohexanone 4.4 0.75 g 0.00375 g   3.82/0.42 g 2.5 × 10¹⁵99.5%   0.5%    2 PHS-B Tic-5c Acetone/Cyclohexanone 3.9 2.25 g 0.0225g  11.45/1.27 g  2.8 × 10¹⁵ 99% 1%  3 PHS-B Tic-5c Acetone/Cyclohexanone3.6 0.75 g 0.015 g  3.81/0.42 g 2.0 × 10¹⁵ 98% 2%  4^(a,b) CBA Tic-5cGlyc Ethox Acetone/2-Pentanone 3.6 2.848 g  0.032 g  0.32 g  11.52/1.28g  9.8 × 10¹⁴ 89% 1% 10%  5^(a) CMM Tic-5c Glyc EthoxAcetone/2-Pentanone 4.2 2.768 g  0.032 g  0.4 g 11.52/1.28 g  5.2 × 10¹⁴86.5% 1% 12.5%    6 CHM Tic-5c Acetone/2-MeOEthanol 4.3 1.78 g 0.02 g7.20/0.80 g 1.3 × 10¹⁶ 99% 1%  7^(a,b) CHM Tic-5c Glyc EthoxAcetone/2-Pentanone 4.8 2.848 g  0.032 g  0.32 g 11.52/1.28 g  1.2 ×10¹⁵ 89% 1% 10%  8^(a,b) CHM Tic-5c Glyc Ethox Oil Blue NAcetone/Cyclohexanone 5.1 1.74 g 0.02 g 0.2 g 0.04 g  7.20/0.80 g 4.6 ×10¹⁴ 87% 1% 10%  2%  9 CHM Tic-5c Glyc Ethox SrTiO₃ (Ald)Acetone/2-MeOEthanol 6.8 1.18 g 0.02 g 0.2 g 0.6 g 7.20/0.80 g 2.1 ×10¹⁴ 59% 1% 10% 30% 10 CHM Tic-5c Glyc Ethox SrTiO₃ (TPL)Acetone/2-MeOEthanol 4.5 1.18 g 0.02 g 0.2 g 0.6 g 7.20/0.80 g 2.1 ×10¹⁴ 59% 1% 10% 30% 11 CHM Tic-5c SrTiO₃ (Ald) Acetone/Cyclohexanone 5.51.38 g 0.02 g 0.6 g 7.20/0.80 g 4.3 × 10¹⁴ 69% 1% 30% 12^(a) PVA Tic-5cAcetone/2-MeOEthanol 3.4 3.168 g  0.032 g  10.8/1.28 g  3.8 × 10¹⁵ 99%1% ^(a)Coated on 50% T Cr Blue PET donor substrate. ^(b)Coated on 50% TNi PET-MB donor substrate. Wt % refers to wt % of the solids in thefinal dry formulation. Abbreviations: PHS-B: Branched PHS homopolymer;DuPont Electronic Technologies; CBA: PHS copolymer with butyl acrylate,Maruzen; CMM: PHS copolymer with methyl methacrylate; Maruzen; CHM: PHScopolymer with hydroxyethyl methacrylate; Maruzen; PVA:Poly(vinylacetate) from Aldrich (catalog no. 18,949-9) with M_(w) ~83,000 and T_(g) ~ 30° C.; Glyc Ethox: Glycerol Ethoxylate from Aldrich(catalog no. 441864) with average M_(n) ~1,000; Oil Blue N: Aldrich Cat.No. 391557; Strontium titanate nanoparticles: ~50 nm from Aldrich andTPL as indicated; 2-MeOEthanol: 2-MethoxyEthanol.

TABLE B Novolac ® Dielectric Layer Compositions and ElectricalProperties Dielectric Other Constant Polymer IR Dye Additives (at 10³Hz) Amount Amount Amount Solvent Resistivity Ex. Wt % Wt % Wt % AmountOhm-cm 13^(a) HRJ14198 Tic-5c Zonyl FSO 2-Butanone 3.9 5.91 g 0.09 g0.03 g  24.00 g  3.0 × 10¹⁵ 97.9%   1.5%   0.6%  14^(a) HRJ14198 Tic-5c2-Butanone 3.9 1.98 g 0.02 g 8.00 g 2.1 × 10¹⁵ 99% 1% 15^(a) HRJ14198Tic-5c Acetone/2-MeOEthanol 4.0 1.98 g 0.02 g 7.20/0.80 g     8.8 × 10¹⁵99% 1% 16^(a) HRJ14198 Tic-5c SrTiO₃ (Ald) 2-Butanone 5.2 1.38 g 0.02 g0.6 g 8.00 g 1.2 × 10¹⁴ 69% 1% 30% 17^(a) HRJ14198 Tic-5c SrTiO₃ (TPL)Acetone/2-MeOEthanol 6.7 1.38 g 0.02 g 0.6 g 7.20/0.80 g     1.1 × 10¹⁶69% 1% 30% 18^(a) HRJ1583 Tic-5c 2-Butanone 3.6 1.98 g 0.02 g 8.00 g 2.7× 10¹⁴ 99% 1% 19^(a) HRJ1583 Tic-5c SrTiO₃ (TPL) 2-Butanone 13.7  0.78 g0.02 g 1.2 g 8.00 g 4.8 × 10¹⁸ 39% 1% 60% ^(a)Coated on 50% T Cr BluePET donor substrate. Wt % refers to wt % of the solids in the final dryformulation. Abbreviations: HRJ14198 and HRJ1583 are Novolac ® resinspurchased from Schenectady International Inc.; 2-MeOEthanol:2-MethoxyEthanol. Strontium titanate nanoparticles: ~50 nm from Aldrichand TPL as indicated.

TABLE C Donor Elements and Printing Parameters of Dielectric LayerCompositions of Tables A & B Optimal Power Step Transfer^(d) Ex. DonorReceiver DS^(a) SD^(b) SR^(c) (W) (W) (W)  4^(e) 50% T Ni PET-MB R-2 10070 0.60 3.0-8.0 0.50 5.0  7^(e) 50% T Ni PET-MB R-2 100 70 0.60 3.0-8.00.50 5.0 12^(f) 50% T Cr Blue PET R-1 100 105 0.28 3.0-8.0 0.50 5.0 1350% T Cr Blue PET R-1/Pani 200 105 0.31 3.0-8.0 0.50 6.0 17 50% T CrBlue PET R-1 170 105 0.33  3.0-12.5 0.50 8.5 19^(g) 50% T Cr Blue PETR-1/Pani 170 105 0.32  6.5-11.5 0.50 8.5-10.5^(h) ^(a)DS: drum speed.^(b)SD: surface depth. ^(c)SR: surface reflectivity. ^(d)Optimaltransfer refers to largely complete transfer of the dielectric withminimal defects. ^(e-g)In the donor element fabrication, thecompositions are the same as reported in Tables A and B with theexception of some solvent variation: ^(e)2-Pentanone was replaced bycyclohexanone. ^(f)2-Methoxyethanol was replaced by 2-butoxyethanol.^(g)2-Butanone was replaced by a 9:1 mixture of acetone/2-pentanone.^(h)8.5 W: complete onto receiver; 10.5 W: complete onto conductor layerand receiver.

Examples 20-23 and Comparative Example C-1 Commercial Styrene-AcrylicPolymers as Dielectric Layers

Dielectric layers comprising commercial styrene-acrylic polymers wereprepared from the components reported in Table D according to thegeneral procedure given above for the preparation of aqueous-baseddielectrics. The electrical properties of these dielectrics weredetermined through resistivity measurements and through characterizationof electrical performance in printed TFT's and capacitors.

Joncryl 95 (J-95) acrylic latex is from Johnson Polymer with Tg of 43°C., an acid number of 70, and a Z-average particle size of 40.5 nm.Joncryl 1915 (J-1915) acrylic latex is from Johnson Polymer with a Tg of43° C., an acid number of 66, and a Z-average particle size of 75.6 nm.Joncryl 63 (J-63) styrene acrylic resin is from Johnson Polymer with aTg of 73° C., an acid number of 213, and a Mw of 12,000.

In a printed TFT array, a Joncryl 1915 (Examples 22 and 60) dielectricgave a high yield of working transistors (>96%) with low off current[median Log(I_(off))=−11.5]. Joncryl 95 alone (Examples 21 and 61) andin combination with Joncryl 63 (Examples 23 and 63) in dielectrics gavetransistors with a median mobility of 0.05 cm²V⁻¹s⁻¹ and median Log(I_(off)) of −10 or less. Joncryl 63 as the sole dielectric polymer gavea resistivity less than 10¹⁴ ohm-cm (Comparative Example 1).

TABLE D Dielectric Layer Compositions and Electrical PropertiesUtilizing Commercial Styrene-Acrylic Polymers Dielectric ConstantPolymer Polymer IR Dye Surfactant Other (at 10³ Hz) Amount Amount AmountAmount Additives Solvent pH Resistivity Ex. Wt % Wt % Wt % Wt % Wt %Amount OD Ohm-cm 20 J-95 SDA 4927 Byk 345 H₂O 8.16 3.2 12.600 g 0.060 g0.104 g  9.201 g 0.40 3.6 × 10¹⁵ 95.9% 1.5% 2.6% 21 J-95 SDA 2860 Byk348 H₂O 7.99 ^(a)Ex. 61 16.780 g 0.290 g 0.055 g 12.840 g 0.98 93.6%5.4% 1.0% 22 J-1915 SDA 2860 Byk 348 H₂O 8.67 ^(a)Ex. 60 11.430 g 0.290g 0.055 g 18.170 g 93.6% 5.4% 1.0% 23 J-95 J-63 SDA 2860 Byk 348 H₂O8.22 ^(a)Ex. 62  8.390 g 8.370 g 0.105 g 0.050 g 11.980 g 0.70 48.5%48.5% 2.0% 1.0% C-1^(b) J-63 SDA 2860 Zonyl FSN Glyc Ethox H₂O/2BuO-8.60 5.9 × 10¹³ 12.600 g 0.081 g 0.100 g 0.100 g Ethanol 0.75 2.0% 1.0%2.5% 8.89/0.941 g    ^(a)Electrical performance was characterized by theelectrical performance of printed TFT's utilizing this dielectric asreported in the indicated Examples. ^(b) Resistivity was determined bythe ITO Method, as described above. Wt % refers to wt % of the solids inthe final dry formulation. Abbreviations: OD: Optical density of ~2.3micron film; Glyc Ethox: Glycerol Ethoxylate; 2BuOEthanol:2-ButoxyEthanol.

Examples 24-34

Dielectric Layers with SDA 2860, Acrylic Latex and Various Surfactants

Dielectric layers comprising various amounts of SDA 2860, mixtures ofvaried Tg acrylic latex with 0-3% acid, and various surfactants wereprepared from the components reported in Table E according to thegeneral procedure given above for the preparation of aqueous-baseddielectrics.

TABLE E Acrylic Dielectric Layer Compositions and Electrical PropertiesDielectric Constant Polymer Polymer IR Dye Surfactant (at 10³ Hz) AmountAmount Amount Amount Solvent pH Resistivity Ex. Wt % Wt % Wt % Wt %Amount OD Ohm-cm 24 LH-3 LL-3 SDA 2860 Byk 345 H₂O/2BuO- 4.44 3.3  12.78g  2.44 g 0.290 g 0.055 g Ethanol 3.2 × 10¹⁵ 78.6% 15.0% 5.4% 1.0%12.95/1.39 g 25 LH-3 LL-3 SDA 2860 Zonyl FSN H₂O/2BuO- 4.81 3.2 12.780 g2.440 g 0.290 g 0.130 g Ethanol 2.5 × 10¹⁵ 78.6% 15.0% 5.4% 1.0%12.95/1.30 g 26 LH-3 LL-3 SDA 2860 TG Surf. H₂O/2BuO- 4.60 3.3 12.780 g2.440 g 0.290 g 0.065 g Ethanol 1.9 × 10¹⁵ 78.6% 15.0% 5.4% 1.0%12.95/1.38 g 27 LH-3 LL-3 SDA 2860 H₂O/2BuO- 4.27 3.1 12.780 g 2.440 g0.290 g Ethanol 3.4 × 10¹⁵ 79.4% 15.2% 5.5% 12.70/1.39 g 28 LH-3 LL-3SDA 2860 Zonyl FSA H₂O/2BuO- 6.26 3.2  12.78 g  2.44 g 0.290 g 0.220 gEthanol 0.8 1.2 × 10¹⁴ 77.6% 14.8% 5.3% 1.0% 13.08/1.39 g 29 LH-3 LL-3SDA 2860 Byk 345 H₂O/2BuO- 4.93 3.2 11.120 g 4.120 g 0.290 g 0.055 gEthanol 0.81 1.9 × 10¹⁵ 68.3% 25.3% 5.4% 1.0% 12.96/1.38 g 30 LH-3 LL-3SDA 2860 Byk 345 H₂O/2BuO- 4.58 3.2  13.59 g  1.63 g 0.290 g 0.055 gEthanol 4.3 × 10¹⁵ 83.6% 10.0% 5.4% 1.0% 12.95/1.39 g 31 LH-3 LL-3 SDA2860 Byk 345 H₂O/2BuO- 4.59 3.3  14.40 g 0.820 g 0.290 g 0.055 g Ethanol3.5 × 10¹⁵ 88.5% 5.0% 5.4% 1.0% 12.95/1.39 g 32 LH-1 LL-1 SDA 2860 Byk345 H₂O/2BuO- 4.48 ^(a)Ex. 64, 65, & 67 10.310 g 4.930 g 0.290 g 0.055 gEthanol 63.3% 30.3% 5.4% 1.0% 12.96/1.39 g 33 LH-0 LL-0 SDA 2860 Byk 345H₂O/2BuO- 7.35 ^(a)Ex. 58 11.120 g 4.120 g 0.290 g 0.055 g Ethanol 68.3%25.3% 5.4% 1.0% 12.96/1.38 g 34 LH-1 LL-1 SDA 2860 Byk 348 H₂O 4.60^(a)Ex. 59 10.310 g 4.930 g 0.290 g 0.055 g 14.35 g 0.95 63.3% 30.3%5.4% 1.0% ^(a)Electrical performance was characterized by the electricalperformance of printed TFT's utilizing this dielectric as reported inthe indicated Examples. Wt % refers to wt % of the solids in the finaldry formulation. Abbreviations: OD: Optical density of ~2.3 micron film;2BuOEthanol: 2-ButoxyEthanol; TG Surf.: TG Surfactact (Air Products).

Examples 35-42

Dielectric Layers with SDA 4927, Acrylic Latex, and Various Surfactants,Additives and Cosolvents

Dielectric layers comprising various amounts of SDA 4927, varied Tgacrylic latex with 1-3% acid, surfactants, co-solvents andtriethanolamine ethoxylate (TEOE) were prepared from the componentsreported in Table F according to the general procedure given above forthe preparation of aqueous-based dielectrics.

TABLE F Acrylic Dielectric Layer Compositions and Electrical PropertiesDielectric Constant Polymer Polymer IR Dye Surfactant Other (at 10³ Hz)Amount Amount Amount Amount Additives Solvent pH Resistivity Ex. Wt % Wt% Wt % Wt % Wt % Amount OD Ohm-cm 35 LH-3 LL-3 SDA 4927 Zonyl FSA TEOEH₂O/2BuO- 5.94 3.2 12.78 g 2.44 g 0.130 g 0.200 g 0.043 g Ethanol 0.413.3 × 10¹⁵ 80.4% 15.4% 2.5% 1.0% 0.8% 12.04/1.35 g 36 LH-3 LL-3 SDA 4927Zonyl FSA TEOE H₂O/2BuO- 5.40 3.3 12.78 g 2.44 g 0.260 g 0.200 g 0.086 gEthanol 0.80 7.6 × 10¹⁴ 77.8% 14.9% 4.8% 0.9% 1.6% 12.64/1.30 g 37 LH-3LL-3 SDA 4927 Byk 346 TEOE H₂O/2BuO- 3.17 3.1 11.11 g 4.11 g 0.080 g0.100 g 0.023 g Ethanol 0.29 6.2 × 10¹⁵ 70.8% 26.2% 1.5% 1.0% 0.4%12.07/1.35 g 38 LH-3 LL-3 SDA 4927 Byk 346 TEOE H₂O/2BuO- 3.35 3.1 11.11g 4.11 g 0.130 g 0.100 g 0.043 g Ethanol 1.7 × 10¹⁵ 69.9% 25.8% 2.5%1.0% 0.8% 12.40/1.35 g 39 LH-3 LL-3 SDA 4927 Byk 346 TEOE H₂O/iPrOH 3.493.1 11.11 g 4.11 g 0.130 g 0.100 g 0.043 g 12.40/1.35 g 0.51 2.6 × 10¹⁵69.9% 25.8% 2.5% 1.0% 0.8% 40 LH-3 LL-3 SDA 4927 Byk 346 TEOE H₂O/2BuO-3.36 3.4 11.11 g 4.11 g 0.185 g 0.100 g 0.061 g Ethanol 0.73 1.9 × 10¹⁵68.9% 25.5% 3.5% 1.0% 1.1% 12.73/1.35 g 41 LH-3 LL-3 SDA 4927 Byk 346TEOE H₂O/2BuO- 3.29 3.2 11.11 g 4.11 g 0.265 g 0.100 g 0.088 g Ethanol1.03 1.2 × 10¹⁵ 67.5% 25.0% 4.9% 1.0% 1.6% 13.22/1.35 g 42 LH-3 SDA 4927Zonyl FSA H₂O/2BuO- 5.25 2.8 16.068 g  0.040 g 0.224 g Ethanol 2.4 ×10¹⁴ 98.2% 0.7% 1.0% 11.48/1.99 g Wt % refers to wt % of the solds inthe final dry formuation. Abbreviations: OD: Optical density of ~2.3micron film; 2BuOEthanol: 2-ButoxyEthanol; TEOE: Triethanolamineethoxylate from Aldrich (cat. no. 416584).

Example 43 and Comparative Examples C-2 and C-3 Barium Titanate AcrylicDielectric Layers

Dielectric layers comprising acrylic latex and solution-based polymerswere prepared from the components reported in Example 43 of Table Gaccording to the general procedure given above for the preparation ofaqueous-based dielectrics.

Examples C-2 and C-3 are comparative examples prepared according to theprocedure of Example 1 of WO2005/004205. The relatively high acidnumber, solution-based acrylic dispersant (Acid No.=106) was utilized asthe sole dielectric polymer and gave low resistivities (10¹² ohm-cm)when combined with barium titanate nanoparticles. When the samedispersant and barium titanate nanoparticles were combined with a lowacid number latex, a high resisitivity dielectric was obtained asillustrated in Example 43.

Preparation of BaTiO₃ dispersions for Examples 43, C-2 and C-3: TheBaTiO₃ pigment dispersion was prepared according to the method of WO2005/004205 as follows: Materials included Cabot BaTiO₃ nanoparticles(Cabot Corporation, Boston, Mass.) and DR-3 (a graft copolymer with anacrylate backbone, 69%, and methacrylate arms, 31%). The specificstructure of the backbone is n-butyl acrylate/methyl acrylate/acrylicacid (45.5/45.5/9), and that of the arms is methylmethacrylate/methacrylic acid (71.25/28.75), and is described inWO9421701A1; M_(w)=24,000; M_(n)=9500; Arm M_(n)˜1500-2000. The pigmentdispersion was prepared at 25% solids loading, with apigment-to-dispersant ratio (P/D) of 2.0, as described in US 5,231,131.A mixture of 236.16 g of water, 48.56 g of dispersant solution, and 6.92g of 2-amino-2-methyl-1-propanol was charged, along with 58.36 g ofBaTiO₃, to an attritor (Appol® Trick Titanium, Troy, Mich.). Theattritor contained 850 g of 0.8-1.0 micron zirconia media. The mixturewas processed for 12 h, keeping the temperature below 38° C. Filtrationthrough a one-micron filter produced the pigment dispersion. Dispersionsof P/D-1.5 and P/D-8 were prepared in the same manner.

TABLE G Acrylic Dielectric Layer Compositions and Electrical PropertiesDielectric Other Constant Polymer IR Dye Surfactant Additives 10³ HzAmount Amount Amount Amount Solvent Resistivity^(a) Ex. Wt % Wt % Wt %Wt % Amount Ohm-cm 43 LH-3-2GA SDA 4927 Zonyl FSA BaTiO₃ & H₂O/2BuO- 5.32.25 g   0.026 g 0.005 g DR3 Ethanol 2.4 × 10¹⁴   49.1%  1.7% 0.1% P/D-84.25/0.50 g 2.97 g 15.12% 49.1% C-2 BaTiO₃ 8.6 &DR3 7 × 10¹² P/D-1.5 1 g100% C-3 BaTiO₃ 21.3  &DR3 1 × 10¹² P/D-8 1 g 100% ^(a)Electricalmeasurements were obtained by spin-coating the dielectric utilizing themethod give above. Wt % refers to wt % of the solids in the final dryformulation.

Examples 44-52

Hydroxyethyl Methacrylate-Containing Dielectrics; Donors with MultilayerDielectrics, Gradient Dielectric Layers, and Interlayers

Example 44

This example illustrates a donor with Topas® copolymer interlayer.Formulations H-1 and H-2 were prepared according to the above generalprocedure for solvent-based dielectrics. T-5013 is Topas® 5013 (Ticona)ethylene-norbornene copolymer with a heat deflection temperature of 130°C., and J-611 is Joncryl 611 styrene acrylic resin (Johnson Polymer),with a Mw of 8100, Acid No.=53, and Tg=50° C. The Topas® copolymerinterlayer formulation H-1 (3 mL) was coated on a 50% T Cr Blue donorsubstrate using a 2CN coating rod and a coating speed of 9.8 ft/min. Thefilm was dried for 6 min. at 45° C. The J-611 transfer layer formulationH-2 (7 mL) was coated on top of the T-5013 interlayer using a 7CNcoating rod and a coating speed of 9.8 ft/min. The film was dried for 6min at 45° C. The ability to thermal-transfer this dielectric onto aconductor and receiver surface was demonstrated following the proceduresfor printing dielectric blocks over conductor stripes given underExamples 1-19. The conductor utilized was Ag/Elv-CN8 and was printed inthe stripe pattern at ds 160 at 7.6 W. The dielectric was printed at ds180 at 8.25 to 10.75 W in 0.25 W step increments. Transfer of thedielectric was largely complete onto both the receiver and silversurfaces at 8.75 W.

Example 45

This example illustrates a tri-layer dielectric donor with gradient dyelayers. Using a CV coater, formulation H-3 (3 mL) was coated onto a 40%T Cr Blue donor substrate with a CN-3 rod at 9.8 ft/min and then driedfor 6 min. at 45° C. This procedure was repeated for formulations H-4and H-5, coating H-4 on top of H-3 and H-5 on top of H-4 to give atrilayer dielectric with gradient dye layers. Thermal transfer as inexample 66 yielded a TFT with the dielectric layer with the lowest dyeloading adjacent to the semiconductor.

Example 46

This example illustrates a bi-layer dielectric donor with gradient dyelayers. Formulation H-6 (4 mL) was coated, using a CV coater, onto a is40% T Cr Blue donor substrate with a CN-4 rod at 9.8 ft/min and thendried for 6 min. at 45° C. This procedure was repeated for formulationH-5, coating H-5 on top of H-6 to give a bi-layer dielectric withgradient dye layers. Thermal transfer yielded a bottom-gate TFT with thedielectric surface with the lowest dye loading adjacent to thesemiconductor. Conductor donors and printing conditions were analogousto Example 66 with the exception that the dielectric layer was printedat 9.75 W.

Example 47

This example illustrates a tri-layer dielectric donor with gradient dyelayers and a Layer B. Using a CV coater, formulation H-7 (3 mL) iscoated onto a 40% T Cr Blue donor substrate with a CN-3 rod at 9.8ft/min and then dried for 6 min. at 45° C. This procedure is repeatedfor formulations H-4 and H-5, coating H-4 on top of H-7 and H-5 on topof H-4 to give a trilayer dielectric with gradient dye layers. Thermaltransfer as in Example 66 yields a bottom-gate TFT with the acid- anddye-free dielectric surface (Layer B) adjacent to the semiconductor.

Example 48

This example illustrates a bi-layer dielectric donor with a carbonblack-containing layer. Using a CV coater, formulation H-8 (3 mL) wascoated onto an Organic LTHC Blue donor substrate with a CN-3 rod at 7.1ft/min and then dried for 6 min. at 45° C. Formulation H-9 (4 mL) wasthen coated on top of H-8 with a CV coater at 7.1 ft/min using a CN-4rod to give a bi-layer dielectric. Thermal transfer as in Example 66yields a bottom-gate TFT with the smooth carbon-black-free dielectricsurface adjacent to the semiconductor.

Example 49

This example illustrates a bi-layer dielectric donor with a strontiumtitanate-containing layer. Using a CV coater, formulation H-8 (3 mL) wascoated onto an Organic LTHC Blue donor substrate with a CN-2 rod at 7.1ft/min and then dried for 6 min. at 45° C. Formulation H-10 (5 mL) wasthen coated on top of H-8 with a CV coater at 9.8 ft/min using a CN-5rod to give a bilayer dielectric. Thermal transfer as in Example 66yields a bottom-gate TFT with the smooth, nanoparticle-free dielectricsurface is adjacent to the semiconductor.

Example 50

This example illustrates bi-layer dielectric donor with gradientnanoparticle layers. Using a CV coater, formulation H-10 (3 mL) iscoated onto an Organic LTHC Blue donor substrate with a CN-2 rod at 7.1ft/min and then dried for 6 min. at 45° C. Formulation H-11 (5 mL) isthen coated on top of H-10 with a CV coater at 9.8 ft/min using a CN-5rod to give a bilayer dielectric. Thermal transfer as in Examples 66yields a bottom-gate TFT with the smooth dielectric surface with thelower nanoparticle loading adjacent to the semiconductor.

Example 51

This example illustrates bi-layer dielectric donor with nanoparticlelayer and Layer B. Using a CV coater, formulation H-7 (3 mL) is coatedonto a 40% T Cr Blue donor substrate with a CN-2 rod at 7.1 ft/min andthen dried for 6 min. at 45° C. Formulation H-11 (5 mL) is then coatedon top of H-7 with a CV coater at 9.8 ft/min using a CN-5 rod to give abilayer dielectric. Thermal transfer as in Examples 66 yields a TFT withthe acid- and dye-free dielectric surface adjacent to the semiconductor.

Example 52

This example illustrates a hydroxyethylmethacrylate-containingdielectric. Using a CV coater, formulation H-12 (7 mL) was coated onto a40% T Cr Blue donor substrate with a CN-7 rod at 9.8 ft/min and thendried for 6 min. at 45° C.

TABLE H Formulations for Interlayers and Multilayer Dielectrics PolymerPolymer IR Dye Surfactant Other Amount Amount Amount Amount AdditivesSolvent pH No. Wt % Wt % Wt % Wt % Wt % Amount OD H-1^(a) T-5013Cyclohexane  5.000 g 95.00 g  100% H-2^(a) J-611 Tic-5c Zonyl FSO-Acetone  3.790 g 0.040 g 100 17.73 g 97.7% 1.0% 0.050 g 1.3% H-3^(b)LH-1 LL-1 SDA 4927 Byk 348 TEOE H₂O 3.93 11.110 g 4.110 g 0.080 g 0.100g 0.023 g 13.83 g 70.2% 26.0% 1.5% 1.9% 0.40% H-4^(b) LH-1 LL-1 SDA 4927Byk 348 TEOE H₂O 3.68 11.110 g 4.110 g 0.185 g 0.055 g 0.061 g 14.55 g68.9% 25.5% 3.5% 1.0%  1.1% H-5^(b) LH-1 LL-1 SDA 4927 Byk 348 TEOE H₂O3.52 22.220 g 8.220 g 0.530 g 0.110 g 0.176 g 30.100 g  67.5% 25.0% 4.9%1.0% 1.6% H-6^(b) LH-1 LL-1 SDA 4927 Byk 348 TEOE H₂O 3.30 11.110 g4.110 g 0.080 g 0.055 g 0.023 g 13.89 g 70.8% 26.2% 1.5% 1.1% 0.40%H-7^(c) LH-0 LL-0 Byk 348 H₂O 11.110 g 4.110 g 0.055 g 13.02 g 72.2%26.7% 1.1% H-8^(b) LH-1 LL-1 SDA 2860 Byk 348 H₂O 3.50 10.310 4.9300.080 g 0.050 g 13.38 65.9% 31.5   1.6% 1.0% H-9^(b) LH-1 LL-1 SDA 2860Byk 348 Black H₂O 7.00 10.310 g 4.930 0.085 g 0.050 g 32B56^(d) 13.3862.3% 29.8% 1.6% 0.9% 0.910 g 5.5 wt % H-10^(b) LH-1 LL-1 SDA 2860 Byk348 SrTiO₃ H₂O 8.74 10.310 g 4.930 0.085 g 0.050 g (TPL)^(e) 20.17 51.2%24.5% 1.3% 0.8% 1.400 g 21.1% H-11^(b) LL-1 SDA 2860 Byk 348 SrTiO₃ H₂O1.250 0.043 g 0.043 g (TPL)^(f)  18.614  9.7% 1.0% 1.0% 3.549 g 83.4%H-12^(b) LHEA-6 SDA 2860 Byk 345 PEG- H₂O/2BuO- 4.14 15.240 g 0.290 g0.055 g OMe₂ ^(g) Ethanol 0.88 91.9% 5.3 wt % 1.0% 0.100 g 13.42/1.39g     (1.8 wt %) Wt % refers to wt % of the solids in the final dryformulation. Prepared according to the above general procedures for^(a)solvent-based and ^(b)aqueous dielectric formulations ^(c)Prepareaccording to the above general procedures for aqueous dielectricformulations. ^(d)Carbon Black Acroverse Paste 32B56 (33 wt %; PennColor). ^(e)Formulation also contained 0.007 g (0.1 wt %) of SurfynolDF110D (Air Products) and 0.074 g of Disperbyk 190 (Byk Chemie). TheSurfynol, Disperbyk, SrTiO₃ nanoparticles and.1.850 g of the water wereprobe-sonicated in a vial placed in an ice bath for 3 × 10 min with 5min intervals between sonication cycles and then rolled at least one daywith 0.5 mm zirconia media prior to adding to the formulation.^(f)Formulation also contained 0.019 g (0.4 wt %) of Surfynol DF110D and0.188 g (4.4 wt %) of Disperbyk 191 (Byk Chemie). The Surfynol,Disperbyk, SrTiO₃ nanoparticles and 4.694 g of the water wereprobe-sonicated in a vial placed in an ice bath for 3 × 10 min with 5min intervals between sonication cycles and then rolled at least one daywith 0.5 mm zirconia media prior to adding to the formulation.^(g)Abbreviations: OD: Optical density of ~2.3 micron film; 2BuOEthanol:2-ButoxyEthanol; TEOE: Triethanolamine ethoxylate from Aldrich (cat. no.416584); PEG-OMe₂ polyethyleneglycol dimethylether (Aldrich 44,590-8);Strontium titanate nanoparticles: ~50 nm from TPL.

Examples 53-67 and Comparative Example-4 C Composition, PrintingParameters and Characterization of TFT's and TFT Arrays

The TFT's and TFT arrays reported in Examples 53-67 and C-4 wereprepared according⁻to the procedures disclosed in the sections entitled“General procedures for printing bottom-gate transistors with associatedcapacitors, bus lines and test pads” and the “General procedure forsemiconductor evaporation.” Details regarding donors and receivers,printing conditions, and. TFT performance are given in Table 11-3 andTable J 1-3. Comparative Example C-4, where the dielectric is laminated,demonstrates that dielectrics that have significant quantities of IRabsorbers and that have been processed through thermal transfer can beused to produce TFT's with comparable and, at times, better performanceand yield than TFT's produced with a similar dielectric without the IRabsorber and processed through a milder lamination process.

TABLE I-1 Donors for TFT's Source-Drain Ex Gate Donor Dielectric DonorDonor Semiconductor 53 Pani-7% Ex. 29 Pani-7% Evaporated Additional airOrganic LTHC Green PET donor 40 min Pentacene dry for days substrate; 30min additional dry at additional dry at 45° C. 45° C. 54 mPani-7%-b Ex.29 Pani-7% Evaporated 40% T Cr Blue PET donor Pentacene substrate; 30min additional dry at 45° C. 55 Pani-7% Ex. 41 w/o TEOE Pani-7%Evaporated 40% T Cr Blue PET; 40 min Pentacene additional dry at 45° C.56 Pani-7% Ex. 41 w/o TEOE Pani-7% Evaporated 40% T Cr Blue PET donorSC-H1 substrate; 40 min additional dry at 45° C. 57 Pani-7% Ex. 41 w/Byk345 Pani-7% Evaporated Additional air 40% T Cr Blue PET donor 40 minPentacene dry for days substrate; 40 min additional dry at additionaldry at 45° C. 45° C. Receiver: 5 mil Kapton HN (DuPont).

TABLE I-2 Printing Patterns and Parameters for TFT's TFT DielectricPrinting Parameters Ex Pattern Pattern Gate Dielectric Source-Drain 53 1Solid DS = 205 at 5.70 W DS = 205 at 8.35 W DS = 205 at 5.75 W 54 1Solid DS = 205 at 5.25 W DS = 120 at 5.75 W DS = 205 at 5.35 W 55 1Solid DS = 205 at 5.7 W DS = 160 at 7.3 W DS = 205 at 5.75 W 56 1 SolidDS = 205 at 5.7 W DS = 200 at 8.5 W DS = 205 at 5.75 W 57 1 Solid DS =205 at 5.7 W DS = 160 at 7.5 W DS = 205 at 5.75 W

TABLE I-3 Electrical Performance of TFT's Mobility V_(Th) I_(on) I_(off)Ex (cm²V⁻¹s⁻¹) (V) (A) (A) I_(on)/I_(off) 53 0.120 −5.60 1.70E−06 9.7E−12 1.80E+05 54 0.060 −6.00 8.00E−07 8.00E−13 1.00E+06 55 0.1804.70 3.60E−06 2.10E−11 1.70E+05 56 0.536 −8.20 6.59E−06 3.16E−112.10E+05 57 0.120 −1.80 2.10E−06 1.00E−11 2.00E+05

TABLE J-1 Donors for Printed TFT Arrays Ex Gate Donor Dielectric DonorSource-Drain Donor Semiconductor 58 Ag/Elv-#8 Ex. 33 Pani-7% Evaporated40 min 40% T Cr Blue PET 40 min additional dry at Pentacene additionaldry donor substrate; 40 min 45° C. followed by air dry at 45° C.additional dry at 45° C. for 3 days 59 Pani-7% Ex. 34 Pani-7% EvaporatedAdditional air WPTS ® 3737^(a) 40 min additional dry at Pentacene dryfor days 50° C. 60 Ag/Elv-CN7 Ex. 22 Pani-7% Evaporated 40 min 40% T CrBlue PET 40 min additional dry at Pentacene additional dry donorsubstrate; 40 min 50° C. at 50° C. additional dry at 45° C. 61mPani-7%-b Ex. 21 Pani-7%^(c) Evaporated 40% T Cr Blue PET Pentacenedonor substrate; 40 min additional dry at 45° C. 62 Pani-7% Ex. 23Pani-7% Evaporated 10 min 40% T Cr Blue PET 40 min additional dry atPentacene additional dry donor substrate; 40 min 45° C. at 50° C.additional dry at 45° C. 63 Pani-7%^(a) Ex. 29 Ag/ElvCNT-#8 Evaporated50% T Cr Blue PET 60 min additional dry at Pentacene donor substrate; 40min 50° C. additional dry at 50° C. 64 mAg/Elv-CN8 Ex. 32 Pani-7%^(c)Evaporated 40 min 50% T Cr Blue PET 40 min additional dry at SC-H1additional dry donor substrate; 40 min 50° C. at 45° C. additional dryat 45° C. 65 mAg/Elv-CN8 Ex. 32 Pani-7%^(c) Evaporated 40 min 50% T CrBlue PET 40 min additional dry at SC-H2 additional dry donor substrate;40 min 50° C. at 45° C. additional dry at 45° C. 66 Ag/Elv-CN8 Ex. 45Pani-7% Evaporated 40 min 40% T Cr Blue PET 40 min additional dry atPentacene additional dry donor substrate; 40 min 50° C. at 50° C.additional dry at 45° C. 67 Ag/Elv-CN7 Ex. 32 Pani-7% Evaporated 60 min40% T Cr Blue PET 40 min additional dry at Pentacene additional drydonor substrate; 40 min 45° C. at 50° C. additional dry at 45° C. C-4Ag/Elv-CN7 LH-10-2GA Pani-7% Evaporated 40 min Laminated from R-3 90 minadditional dry at Pentacene additional dry Receiver^(b) 45° C. at 50° C.Receiver: 5 mil Kapton HN. ^(a)WPTS ® 3737: (WaterProof ® TransferSheet) (DuPont; Towanda, PA). ^(b)Dye-free dielectric of compositionLH-10-2GA was laminated from R-3. ^(c)Following source-drain printingand before evaporation of pentacene, peel defects between the source anddrain electrodes were selectively removed from the receiver togetherwith peel defects along line edges according to the following procedure:A piece of 50% T Cr PET donor substrate was cut to approximately thesame size as the receiver and cleaned with a pressurized nitrogen streamto rid the surface of particle contamination. The receiver was placed ona flat surface, and the Cr-coated substrate was placed on top of thereceiver with the Cr surface contacting the patterned surface of thereceiver. A SDI Dust Removal System-1 roller was rolled over the entirearea of the backside of the Cr-coated substrate in a period ofapproximately 30-90 seconds. The Cr-coated substrate was lifted off ofthe patterned receiver surface. Peel defects the size of thesource-drain channel were visible on the Cr surface when it was examinedunder a microscope at 5x magnification. ^(d)Peel defects were removedfrom the gate layer of this transistor. The procedure is similar to thatused for the source-drain layer under the immediately preceding footnotec with the following exceptions: After removal of the pani gate layerdonor, the receiver was left in place on the drum. The Cr-coated donorwas placed on top of the receiver and peel defects were removed aspreviously described (footnote C).

TABLE J-2 Printing Patterns and Parameters for Printed TFT Arrays TFTDielectric Printing Parameters Ex Pattern Pattern Gate DielectricSource-Drain 58 1 Solid DS = 160 at 7.65 W DS = 160 at 7.35 W DS = 205at 5.75 W 59 2 Solid DS = 205 at 5.6 W Laminated from DS = 205 at 5.20 WWPTS ® at 3 min, 2250 lbs, 80° C. 60 2 Patterned DS = 160 at 6.7 W DS =180 at 8.50 W DS = 205 at 5.45 W 61 3 Solid DS = 205 at 5.6 W DS = 180at 7.75 W DS = 205 at 5.75 W 62 3 Solid DS = 205 at 5.7 W DS = 180 at7.70 W DS = 205 at 5.75 W 63 1 Solid DS = 205 at 5.7 W DS = 160 at 7.50W DS = 160 at 7.30 W 64 2 Solid DS = 160 at 7.8 W DS = 160 at 7.35 W DS= 205 at 5.50 W 65 2 Solid DS = 160 at 7.8 W DS = 160 at 7.35 W DS = 205at 5.50 W 66 2 Solid DS = 160 at 7.6 W DS = 200 at 9.50 W DS = 205 at5.60 W 67 2 Solid DS = 160 at 7.6 W DS = 160 at 7.40 W DS = 205 at 5.60W C-4 2 Solid DS = 160 at 6.75 W Laminated from DS = 205 at 5.45 W R-3at 3 min, 2250 lbs, 80° C.

TABLE J-3 Electrical Performance of Printed TFT Arrays Median MedianMedian Array Mobility V_(Th) I_(off) Median Ex Size (cm²V⁻¹s⁻¹) (V) (A)I_(on)/I_(off) Yield 58 54 0.06 −8 1.0E−11   1E+05 98.1% 59 54 0.010 −151.0E−11 3.2E+04 98.1% 60 54 0.001 −12 3.2E−12 3.2E+03 96.3% 61 108 0.05−7 1.0E−10 3.2E+03 75.9% 62 108 0.05 5 3.2E−11 2.0E+03 72.2% 63 54 0.025 1.0E−10 3.2E+03   100%^(a) 64 108 0.00025 −22 3.2E−12 6.3E+02 76.9% 6554 0.008 −18 6.3E−12 6.3E+02 92.6% 66 54 0.025 −12 6.3E−12 4.0E+04 92.6%67 54 0.07 −5 5.0E−11 2.0E+04 94.4% C-4 54 0.003 −5 1.0E−11 3.2E+0388.9% ^(a)Yield of corresponding capacitor array is also 100%, e.g.,100% of the 54 capacitors have I_(leaks) of less than 1.0E−10 A with amedian I_(leaks) of 3.2E−12 A.

1. A composition, comprising: a) one or more dielectric polymer(s)selected from the group consisting of: acrylic and styrenic polymersselected from the group consisting of: acrylic, styrenic andstyrenic-acrylic latexes, solution-based acrylic, styrenic andstyrenic-acrylic polymers, and combinations thereof;heteroatom-substituted styrenic polymers selected from the groupconsisting of: partially hydrogenated poly(4-hydroxy)styrene,poly(4-hydroxy)styrene, and copolymers of poly(4-hydroxy)styrene withhydroxyethyl(meth)acrylate, alkyl(meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group; phenol-aldehyde (co)polymers and(co)oligomers and combinations thereof; and polyvinyl acetate); and b)about 0.5 wt % to about 10 wt %, based on a dry weight of thecomposition, of one or more near-IR dye(s); wherein a dry layercomprising said composition is has a resistivity of 10¹⁴ ohm-cm orgreater and has an absorption maximum in the range of about 600 to about1200 nm.
 2. The composition of claim 1, consisting essentially of: a)said one or more dielectric polymer(s); and b) said one or more near-IRdye(s).
 3. The composition of claim 1 further comprising: c) a high κnanoparticle fraction up to about 90 wt % based on the dry weight of thecomposition, with the proviso that if the nanoparticle fraction isgreater than 80 wt %, the near-IR dye is less than 6 wt % of thecomposition.
 4. A dielectric layer, having a resistivity of about 10¹⁴ohm-cm or greater, comprising at least one Layer A, comprising: a) oneor more dielectric polymer(s) selected from the group consisting of:acrylic and styrenic polymers selected from the group consisting of:acrylic, styrenic and styrenic-acrylic latexes, solution-based acrylic,styrenic and styrenic-acrylic polymers, and combinations thereof;heteroatom-substituted styrenic polymers selected from the groupconsisting of: partially hydrogenated poly(4-hydroxystyrene),poly(4-hydroxystyrene), and copolymers of poly(4-hydroxystyrene) withhydroxyethyl(meth)acrylate, alkyl(meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group; phenol-aldehyde (co)polymers and(co)oligomers and combinations thereof; and poly(vinyl acetate); and_(—) b) about 0.5 wt % to about 10 wt %, based on a dry weight of LayerA, of one or more near-IR dye(s) having an absorption maximum in therange of about 600 to about 1200 nm within Layer A.
 5. The dielectriclayer of claim 4 wherein said one or more dielectric polymer(s) isselected from acrylic and styrenic polymers selected from the groupconsisting of: acrylic, styrenic and styrenic-acrylic latexes,solution-based acrylic, styrenic and styrenic-acrylic polymers, andcombinations thereof; and comprises one or more latex resins comprisingat least about 85 wt % of monomers selected from the group consistingof: alkyl(meth)acrylate, styrene, and alkyl-substituted styrene whereinthe alkyl group is a C1 to C18 straight or branched chain alkyl group.6. The dielectric layer of claim 4 wherein said one or more dielectricpolymer(s) is selected from acrylic and styrenic polymers selected fromthe group consisting of: acrylic, styrenic and styrenic-acrylic latexes,solution-based acrylic, styrenic and styrenic-acrylic polymers, andcombinations thereof; and comprises a combination of about 20 to about80 wt % of an acrylic or styrenic-acrylic latex fraction and about 20 toabout 80 wt % of a solution-based acrylic or styrenic-acrylic polymerfraction, based on the dry weight of the combination.
 7. The dielectriclayer of claim 4 wherein the near-IR dye(s) is an indocyanine dye. 8.The dielectric layer of claim 4 wherein the near-IR dye(s) is selectedfrom the group consisting of: 3H-indolium,2-[2-[2-chloro-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)ethylidene]-1-cyclopenten-1-yl]ethenyl]-1,3,3-trimethyl-,salt with trifluoromethanesulfonic acid (1:1) having CAS No.[128433-68-1];2-(2-(2-chloro-3-(2-(1,3-dihydro-1,1-dimethyl-3-(4-sulphobutyl)-2H-benz[e]indol-2-ylidene)ethylidene)-1-cyclohexene-1-yl)ethenyl)-1,1-dimethyl-3-(4-sulphobutyl)-1H-benz[e]indolium,inner salt, free acid having CAS No. [162411-28-1]; and indolenine dyesof formula (I) and (II) and resonance structures thereof


9. The dielectric layer of claim 4 comprising two or more Layers A thatare gradient dye layers, each gradient dye layer independently having adry wt % of near-IR dye of about 0.5 to about 10 wt %; wherein at leastone gradient dye layer has a lower wt % of near-IR dye, at least onegradient dye layer has a higher wt % of near-IR dye, and said higher wt% of near-IR dye is a value at least 20% higher than that of the lowerwt % of near-IR dye.
 10. The dielectric layer of claim 4 furthercomprising an additional dielectric layer comprising one or moredielectric polymers characterized by a resistivity of about 10¹⁴ ohm-cmor greater.
 11. The dielectric layer of claim 4 wherein said Layer Afurther comprises a high κ nanoparticle fraction of up to about 90 wt %of Layer A, is with the nanoparticle fraction having a dielectricconstant greater than about 20 and an average particle size of about 5nm to about 500 nm; with the proviso that if the nanoparticle fractionis greater than 80 wt %, the near-IR dye is less than 6 wt % of Layer A.12. The dielectric layer of claim 11 comprising two or more Layers Athat are gradient nanoparticle layers, each gradient nanoparticle layerindependently having a dry wt % of high κ nanoparticle fraction of up toabout 90 wt %; wherein at least one gradient nanoparticle layer has alower wt % of high κ nanoparticle fraction, at least one gradientnanoparticle layer has a higher wt % of high κ nanoparticle fraction,and said higher wt % is a value at least 20% higher than that of thelower wt %.
 13. The dielectric layer of claim 4, wherein said LayerAconsists essentially of: a) said one or more dielectric polymer(s); andb) said one or more near-IR dye(s).
 14. A multilayer thermal imagingdonor comprising: a) a base film; and b) a dielectric transfer layercomprising at least one Layer A comprising: one or more dielectricpolymer(s) selected from the group consisting of: acrylic and styrenicpolymers selected from the group consisting of: acrylic, styrenic andstyrenic-acrylic latexes, solution-based acrylic, styrenic andstyrenic-acrylic polymers, and combinations thereof;heteroatom-substituted styrenic polymers selected from the groupconsisting of: partially hydrogenated poly(4-hydroxystyrene),poly(4-hydroxystyrene), and copolymers of poly(4-hydroxystyrene) withhydroxyethyl(meth)acrylate, alkyl(meth)acrylate, styrene, andalkyl-substituted styrene wherein the alkyl group is a C1 to C18straight or branched chain alkyl group; phenol-aldehyde (co)polymers and(co)oligomers and combinations thereof; and poly(vinyl acetate); andabout 0.5 wt % to about 10 wt %, based on the dry weight of Layer A, ofone or more near-IR dye(s) having an absorption maximum in the range of600 to about 1200 nm within Layer A; wherein the dielectric transferlayer has a resistivity of 10¹⁴ ohm-cm or greater.
 15. The donor ofclaim 14, further comprising an LTHC layer interposed between the basefilm and the dielectric transfer layer.
 16. The donor of claim 15wherein the LTHC layer comprises one or more radiation absorber(s)selected from the group consisting of: metal films selected from Cr andNi; carbon black; graphite; and near-IR dyes with an absorption maximain the range of about 600 to 1200 nm within the LTHC layer.
 17. Thedonor of claim 16, wherein the one or more radiation absorber(s)comprises a near-IR dye(s), with an absorption maximum in the range ofabout 600 to 1200 nm, comprising one or more water-soluble orwater-dispersible radiation-absorbing cyanine compound(s) selected fromthe group consisting of: indocyanines, phthalocyanines, andmerocyanines; and the LTHC layer further comprises one or morewater-soluble or water-dispersible polymeric binders selected from thegroup consisting of: acrylic and styrene-acrylic resins, hydrophilicpolyesters, sulphonated polyesters, and maleic anhydride homopolymersand copolymers
 18. The donor of claim 14 wherein the base film comprisesa polymeric material selected from the group consisting of: polyethyleneterephthalate, polyethylene naphthalate, triacetyl cellulose andpolyimide.
 19. The donor of claim 14 wherein said one or more dielectricpolymer(s) is selected from acrylic and styrenic polymers selected fromthe group consisting of: acrylic, styrenic and styrenic-acrylic latexes,solution-based acrylic, styrenic and styrenic-acrylic polymers, andcombinations thereof; and comprises one or more latex resin(s)comprising at least about 85 wt % of monomers selected from the groupconsisting of: alkyl (meth)acrylate, styrene, and alkyl-substitutedstyrene wherein the alkyl group is a C1 to C18 straight or branchedchain alkyl group.
 20. The donor of claim 14 wherein the one or morenear-IR dye(s) is an indocyanine dye.
 21. The donor of claim 14 whereinthe one or more near-IR dye(s) is selected from the group consisting of:3H-indolium,2-[2-[2-chloro-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)ethylidene]-1-cyclopenten-1-yl]ethenyl]-1,3,3-trimethyl-,salt with trifluoromethanesulfonic acid (1:1) having CAS No.[128433-68-1];2-(2-(2-chloro-3-(2-(1,3-dihydro-1,1-dimethyl-3-(4-sulphobutyl)-2H-benz[e]indol-2-ylidene)ethylidene)-1-cyclohexene-1-yl)ethenyl)-1,1-dimethyl-3-(4-sulphobutyl)-1H-benz[e]indolium,inner salt, free acid having CAS No. [162411-28-1]; and indolenine dyesof formula (I) and (II) and resonance structures thereof


22. The donor of claim 14 wherein the dielectric transfer layercomprises two or more Layers A that are gradient dye layers, eachgradient dye layer independently having a dry wt % of near-IR dye ofabout 0.5 to about 10 wt %; wherein at least one gradient dye layer hasa lower wt % of near-IR dye, at least one gradient dye layer has ahigher wt % of near-IR dye, and said higher wt % of near-IR dye has avalue that is at least 20% higher that that of the lower wt % of near-IRdye.
 23. The donor of claim 15 further comprising an interlayerinterposed between the LTHC layer and the dielectric transfer layercomprising a thermoplastic or thermoset polymer with a Tg greater thanabout 70° C., and characterized by greater than 80% transmission in the600 nm to about 1200 nm wavelength region.
 24. The donor of claim 14wherein, within the dielectric transfer layer, Layer A further comprisesa high κ nanoparticle fraction of up to about 90 wt % of Layer A, withthe nanoparticle fraction having a dielectric constant greater thanabout 20 and an average particle size of about 5 nm to about 500 nm;with the proviso that if the nanoparticle fraction is greater than 80 wt%, the near-IR dye is less than 6 wt % of Layer A.
 25. The donor ofclaim 24 wherein the dielectric transfer layer comprises two or moreLayers A that are gradient nanoparticle layers, each gradientnanoparticle layer independently having a dry wt % of high κnanoparticle fraction of up to about 90 wt %; wherein at least onegradient nanoparticle layer has a lower wt % of high κ nanoparticlefraction, at least one gradient nanoparticle layer has a higher wt % ofhigh κ nanoparticle fraction, and said higher wt % has a value that isat least 20% higher than that of the lower wt %.
 26. The donor of claim14 wherein the base film comprises a light attenuating agent and ischaracterized by an OD of 0.1 or greater at a wavelength of about 350 nmto about 1500 nm.
 27. The donor of claim 14 wherein said dielectrictransfer layer further comprises one or more additional dielectriclayer(s) comprising one or more dielectric polymer(s) characterized by aresistivity of about 10¹⁴ ohm-cm or greater.